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Class ComboDropDown

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    Class ComboDropDown

    Inheritance
    System.Object
    ComboDropDown
    ComboBoxBase
    Implements
    IThemedControl
    System.ComponentModel.ISupportInitialize
    INonClientPaintingSupport
    ISupportOffice2007Theme
    IVisualStyle
    Namespace: Syncfusion.Windows.Forms.Tools
    Assembly: Syncfusion.Shared.Base.dll
    Syntax
    public class ComboDropDown : Control, IThemedControl, ISupportInitialize, INonClientPaintingSupport, ISupportOffice2007Theme, IVisualStyle

    Constructors

    ComboDropDown()

    Creates a new instance of the ComboDropDown class.

    Declaration
    public ComboDropDown()

    Fields

    autoCompleteSuccess

    Declaration
    protected bool autoCompleteSuccess
    Field Value
    Type Description
    System.Boolean

    cachedBackColor

    Cached BackColor of ComboBox.

    Declaration
    protected Color cachedBackColor
    Field Value
    Type Description
    System.Drawing.Color

    cachedForeColor

    Cached BackColor of ComboBox.

    Declaration
    protected Color cachedForeColor
    Field Value
    Type Description
    System.Drawing.Color

    initializing

    Declaration
    protected bool initializing
    Field Value
    Type Description
    System.Boolean

    m_lastFoundIndex

    Declaration
    protected int m_lastFoundIndex
    Field Value
    Type Description
    System.Int32

    m_scrollersFrame

    Declaration
    protected ScrollersFrame m_scrollersFrame
    Field Value
    Type Description
    ScrollersFrame

    Properties

    AllowMouseWheelSelection

    Gets or sets a value indicating whether selection changing can be done using mouse wheel rotation.

    Declaration
    public bool AllowMouseWheelSelection { get; set; }
    Property Value
    Type Description
    System.Boolean

    true if seelction can be changed using mouse wheel; otherwise, false.

    Remarks

    Instead of handling mouse wheel event and handling it, user can set this bool property as per the needs. This property is used to work when the dropdown is not shown and changing selection through mouse wheel.

    AllowQuickSelection

    Gets or sets a value indicating if quick selection on mouse move is on.

    Declaration
    public bool AllowQuickSelection { get; set; }
    Property Value
    Type Description
    System.Boolean

    BackColor

    Gets or sets the back color. (overridden property)

    Declaration
    public override Color BackColor { get; set; }
    Property Value
    Type Description
    System.Drawing.Color

    BackgroundImage

    Specifies the BackgroundImage.(overridden property)

    Declaration
    public override Image BackgroundImage { get; set; }
    Property Value
    Type Description
    System.Drawing.Image

    BackgroundImageLayout

    Gets or sets background image layout.

    Declaration
    public ImageLayout BackgroundImageLayout { get; set; }
    Property Value
    Type Description
    System.Windows.Forms.ImageLayout

    BeforeTouchSize

    Gets/Sets Control size before touch enabled

    Declaration
    public Size BeforeTouchSize { get; set; }
    Property Value
    Type Description
    System.Drawing.Size

    Border3DStyle

    Gets or sets the 3D border style for the control.

    Declaration
    public Border3DStyle Border3DStyle { get; set; }
    Property Value
    Type Description
    System.Windows.Forms.Border3DStyle
    Remarks

    This property is used only when BorderStyle is Fixed3D.

    BorderSides

    Gets or sets the border sides for which you want the 3D border style applied.

    Declaration
    public Border3DSide BorderSides { get; set; }
    Property Value
    Type Description
    System.Windows.Forms.Border3DSide
    Remarks

    This property is used only when BorderStyle is Fixed3D.

    CaseSensitiveAutocomplete

    Indicates whether the search in autocomplete is case-sensitive.

    Declaration
    public bool CaseSensitiveAutocomplete { get; set; }
    Property Value
    Type Description
    System.Boolean

    CharacterCasing

    Specifies the ComboBoxBase control modifies the case of characters as they are typed.

    Declaration
    public virtual CharacterCasing CharacterCasing { get; set; }
    Property Value
    Type Description
    System.Windows.Forms.CharacterCasing

    One of the System.Windows.Forms.CharacterCasing enumeration values that specifies whether the ComboBoxBase control modifies the case of characters. The default is CharacterCasing.Normal.

    ComboBoxRenderer

    Update the renderer for Office2016 style.

    Declaration
    protected virtual ComboBoxAdvRenderer ComboBoxRenderer { get; }
    Property Value
    Type Description
    ComboBoxAdvRenderer

    ContextMenu

    Gets or sets the ContextMenu. (overridden property)

    Declaration
    public override ContextMenu ContextMenu { get; set; }
    Property Value
    Type Description
    System.Windows.Forms.ContextMenu

    CreateParams

    Declaration
    protected override CreateParams CreateParams { get; }
    Property Value
    Type Description
    System.Windows.Forms.CreateParams

    DefaultSize

    Declaration
    protected override Size DefaultSize { get; }
    Property Value
    Type Description
    System.Drawing.Size

    DropDownButton

    Returns the DropDownButton used to draw the drop-down portion of the combo.

    Declaration
    public DropDownButton DropDownButton { get; }
    Property Value
    Type Description
    DropDownButton

    DropDownButtonHeight

    Gets or sets the height of the drop-down button.

    Declaration
    protected int DropDownButtonHeight { get; set; }
    Property Value
    Type Description
    System.Int32

    DropDownStyle

    Gets or sets the style of the combo box.

    Declaration
    public ComboBoxStyle DropDownStyle { get; set; }
    Property Value
    Type Description
    System.Windows.Forms.ComboBoxStyle

    One of the System.Windows.Forms.ComboBoxStyle values. The default is System.Windows.Forms.ComboBoxStyle.DropDown.

    Remarks

    The DropDownStyle property controls the interface that is presented to the user. You can enter a value that allows for a simple drop-down list box, where the list always displays a drop-down list box, where the text portion is not editable and you must select an arrow to view the drop-down, or the default drop-down list box where the text portion is editable and the user must press the arrow key to view the list.

    DropDownWidth

    Gets or sets the drop-down's width.

    Declaration
    public int DropDownWidth { get; set; }
    Property Value
    Type Description
    System.Int32
    Remarks

    The value provided here will be used to determine the width of the drop-down portion. If you do not set a value explicitly, the width of this control will be used as the preferred width.

    To reset your settings on this property, call the ResetDropDownWidth() method.

    DroppedDown

    Indicates whether the combo box is displaying its drop-down portion.

    Declaration
    public bool DroppedDown { get; set; }
    Property Value
    Type Description
    System.Boolean

    True if the drop-down portion is displayed; False otherwise. The default is False.

    EditPortionHeight

    Gets or sets the height of the edit portion.

    Declaration
    protected int EditPortionHeight { get; set; }
    Property Value
    Type Description
    System.Int32

    EnableTouchMode

    Gets or sets value to enable or disable the Touchmode to the controls.

    Declaration
    public bool EnableTouchMode { get; set; }
    Property Value
    Type Description
    System.Boolean
    Remarks

    Scale factor will be updated automatically if scalefactor is equal to 1

    FlatBorderColor

    Gets or sets the color with which the flat border should be drawn.

    Declaration
    public virtual Color FlatBorderColor { get; set; }
    Property Value
    Type Description
    System.Drawing.Color

    A color value. Default is SystemColors.ControlDark.

    Remarks

    This is also the color used to draw the border when the Style property is set to OfficeXP or Office2003.

    FlatStyle

    Gets or sets the flat style appearance of the combo box control.

    Declaration
    public virtual ComboFlatStyle FlatStyle { get; set; }
    Property Value
    Type Description
    ComboFlatStyle

    One of the ComboFlatStyle values. The default value is Standard.

    Remarks

    When you specify System and the application is run in Windows XP, themes will be used to draw this control.

    Use IsThemedOS and IsThemeActive to determine if themes are on during run-time.

    Focused

    Specifies whether the control is focused. (overridden property)

    Declaration
    public override bool Focused { get; }
    Property Value
    Type Description
    System.Boolean

    Font

    Gets or sets the System.Drawing.Font value for the control.

    Declaration
    public override Font Font { get; set; }
    Property Value
    Type Description
    System.Drawing.Font

    ForeColor

    Gets or sets the ForeColor. (overridden property)

    Declaration
    public override Color ForeColor { get; set; }
    Property Value
    Type Description
    System.Drawing.Color

    GrayOnReadOnly

    Gets or sets a value indicating to show the Gray BackColor on ReadOnly is set.

    Declaration
    public bool GrayOnReadOnly { get; set; }
    Property Value
    Type Description
    System.Boolean

    IgnorePopupValueChange

    Declaration
    protected bool IgnorePopupValueChange { get; set; }
    Property Value
    Type Description
    System.Boolean

    IgnoreThemeBackground

    Indicates whether the control will ignore the theme`s background color and draw the BackColor instead.

    Declaration
    public virtual bool IgnoreThemeBackground { get; set; }
    Property Value
    Type Description
    System.Boolean

    IsInitializing

    Gets a value indicating whether this instance is initializing.

    Declaration
    public bool IsInitializing { get; }
    Property Value
    Type Description
    System.Boolean

    IsPopUpControlType

    Check whether the ComboBox is ComboDropDown or ComboBoxAdv

    Declaration
    public bool IsPopUpControlType { get; }
    Property Value
    Type Description
    System.Boolean

    LastCommittedText

    Declaration
    protected string LastCommittedText { get; set; }
    Property Value
    Type Description
    System.String

    MatchFirstCharacterOnly

    This property defines the autocomplete behavior in DropDownList mode.

    Declaration
    public bool MatchFirstCharacterOnly { get; set; }
    Property Value
    Type Description
    System.Boolean
    Remarks

    This property is used when the DropDownStyle is set to DropDownList only.

    MaxLength

    Gets or sets the maximum number of characters allowed in the editable portion of a combo box.

    Declaration
    public int MaxLength { get; set; }
    Property Value
    Type Description
    System.Int32

    The maximum number of characters the user can enter. Default value is 32767.

    MetroBorderColor

    Gets or sets the BorderColor for metro style

    Declaration
    public Color MetroBorderColor { get; set; }
    Property Value
    Type Description
    System.Drawing.Color

    MetroColor

    Gets or sets the metrocolor.

    Declaration
    public Color MetroColor { get; set; }
    Property Value
    Type Description
    System.Drawing.Color

    NeedLayout

    Indicates whether the layout method needs to be called to layout the combo elements.

    Declaration
    public bool NeedLayout { get; }
    Property Value
    Type Description
    System.Boolean
    Remarks

    Internal method. You will not have to call this property explicitly.

    NumberOnly

    Indicates whether users should be forced to enter numbers.

    Declaration
    public virtual bool NumberOnly { get; set; }
    Property Value
    Type Description
    System.Boolean

    True to force numbers; False otherwise.

    Office2007ColorTheme

    Gets or sets office 2007 color theme.

    Declaration
    public Office2007Theme Office2007ColorTheme { get; set; }
    Property Value
    Type Description
    Office2007Theme

    Office2010ColorTheme

    Gets or sets office 2010 color theme.

    Declaration
    public Office2010Theme Office2010ColorTheme { get; set; }
    Property Value
    Type Description
    Office2010Theme

    PopupContainer

    Returns the PopupControlContainer used to host the drop-down list.

    Declaration
    public PopupControlContainer PopupContainer { get; }
    Property Value
    Type Description
    PopupControlContainer

    PopupControl

    The System.Windows.Forms.Control that will be used in the drop-down portion.

    Declaration
    public virtual Control PopupControl { get; set; }
    Property Value
    Type Description
    System.Windows.Forms.Control

    A System.Windows.Forms.Control derived instance.

    PreventHeightChange

    Indicates whether the Height property of the control can be changed.

    Declaration
    protected bool PreventHeightChange { get; set; }
    Property Value
    Type Description
    System.Boolean

    True to prevent height change; False otherwise .

    Remarks

    Note that this property will be frequently set and reset within the control layout. You can use this temporarily to force a particular height on the control.

    ReadOnly

    Indicates whether the text in the edit portion can be changed.

    Declaration
    public virtual bool ReadOnly { get; set; }
    Property Value
    Type Description
    System.Boolean

    If True, the edit portion is not editable by the user; False otherwise.

    RightToLeft

    Gets or sets a value indicating whether control's elements are aligned to support locales using right-to-left fonts.

    Declaration
    public override RightToLeft RightToLeft { get; set; }
    Property Value
    Type Description
    System.Windows.Forms.RightToLeft

    Style

    Gets or sets an advanced appearance and behavior for this control.

    Declaration
    public VisualStyle Style { get; set; }
    Property Value
    Type Description
    VisualStyle

    One of the VisualStyle values. Default is VisualStyle.Default.

    Remarks

    When a non-default style is specified here, it will override the other settings of the control such as BorderSides and FlatStyle. The FlatBorderColor is used to draw the borders for the office styles, when the control is not active.

    The Office2003 style behaves the same as OfficeXP in non-XP systems.

    SuppressDropDownEvent

    Indicates whether to suppress the DropDown Event

    Declaration
    public bool SuppressDropDownEvent { get; set; }
    Property Value
    Type Description
    System.Boolean

    Text

    Gets or sets the text associated with this control.

    Declaration
    public override string Text { get; set; }
    Property Value
    Type Description
    System.String
    Remarks

    When in DropDownList mode, setting this property will also validate the new value against the attached popup control.

    TextAlign

    Gets or sets the alignment of text in this control.

    Declaration
    public virtual HorizontalAlignment TextAlign { get; set; }
    Property Value
    Type Description
    System.Windows.Forms.HorizontalAlignment

    One of the System.Windows.Forms.HorizontalAlignment enumeration values that specifies how text is aligned in the control. The default is HorizontalAlignment.Left.

    Remarks

    You can use this property to align the text within a ComboBoxBase to match the layout of text on your form. For example, if your controls are all located on the right side of the form, you can set the TextAlign property to HorizontalAlignment.Right and the text will be aligned along the right side of the control instead of the default left alignment.

    TextBox

    Returns the System.Windows.Forms.TextBox used to draw the editable text portion of the combo.

    Declaration
    public TextBox TextBox { get; }
    Property Value
    Type Description
    System.Windows.Forms.TextBox

    UseBackColor

    Gets or sets a value to have effect of BackColor

    Declaration
    public bool UseBackColor { get; set; }
    Property Value
    Type Description
    System.Boolean

    UseMetroButtonColor

    Declaration
    public bool UseMetroButtonColor { get; set; }
    Property Value
    Type Description
    System.Boolean

    UseMetroColorsInActiveMode

    Gets or sets a value indicating whether [use metro colors in active mode].

    Declaration
    public bool UseMetroColorsInActiveMode { get; set; }
    Property Value
    Type Description
    System.Boolean

    true if [use metro colors in active mode]; otherwise, false.

    UseMnemonic

    Declaration
    public bool UseMnemonic { get; set; }
    Property Value
    Type Description
    System.Boolean

    UseOffice2007ColorsInActiveMode

    Gets or sets a value indicating whether [use office2007 colors in active mode].

    Declaration
    public bool UseOffice2007ColorsInActiveMode { get; set; }
    Property Value
    Type Description
    System.Boolean

    true if [use office2007 colors in active mode]; otherwise, false.

    Methods

    ApplyScaleToControl(Single)

    Scale the control based on the scale factor passed in the argument.

    Declaration
    public void ApplyScaleToControl(float scaleFactor)
    Parameters
    Type Name Description
    System.Single scaleFactor

    value to scale the factor based upon.

    AttachPopupControl()

    Declaration
    protected virtual void AttachPopupControl()

    AttachScrollersFrame(Control)

    Attaches scrollersFrame to the PopupControl.

    Declaration
    protected void AttachScrollersFrame(Control control)
    Parameters
    Type Name Description
    System.Windows.Forms.Control control

    CommitChanges()

    Declaration
    protected virtual void CommitChanges()

    CreateAccessibilityInstance()

    Declaration
    protected override AccessibleObject CreateAccessibilityInstance()
    Returns
    Type Description
    System.Windows.Forms.AccessibleObject

    CreateDropDownButton()

    Called once to create a DropDownButton for the drop-down button portion of the combo.

    Declaration
    protected virtual DropDownButton CreateDropDownButton()
    Returns
    Type Description
    DropDownButton

    A new instance of a DropDownButton.

    Remarks

    Override this method to provide a custom implementation of a DropDownButton. InitDropDownButton(DropDownButton)

    CreatePopupContainer()

    Called once to create a PopupControlContainer that will host the drop-down list.

    Declaration
    protected virtual PopupControlContainer CreatePopupContainer()
    Returns
    Type Description
    PopupControlContainer

    A new instance of a PopupControlContainer.

    Remarks

    Override this method to provide a custom implementation of the PopupControlContainer. InitPopupContainer()

    CreateScrollersFrame()

    Creates new instance of the scrollersFrame.

    Declaration
    protected ScrollersFrame CreateScrollersFrame()
    Returns
    Type Description
    ScrollersFrame

    CreateTextBox()

    Called once to create a System.Windows.Forms.TextBox for the editable text portion of the combo.

    Declaration
    protected virtual TextBox CreateTextBox()
    Returns
    Type Description
    System.Windows.Forms.TextBox

    A new instance of a System.Windows.Forms.TextBox.

    Remarks

    Override this method to provide a custom implementation of a text box. InitTextBox()

    DefWndProc(ref Message)

    Sends the specified message to the default windows procedure.

    Declaration
    protected override void DefWndProc(ref Message msg)
    Parameters
    Type Name Description
    System.Windows.Forms.Message msg

    DetachPopupControl(Boolean)

    Declaration
    protected virtual void DetachPopupControl(bool disposing)
    Parameters
    Type Name Description
    System.Boolean disposing

    DetachScrollersFrame()

    Detaches scrollersFrame from the PopupControl.

    Declaration
    protected void DetachScrollersFrame()

    DetermineHeightsBasedOnFont(Graphics, ref Int32)

    Determines the heights of certain portions of this control.

    Declaration
    protected virtual void DetermineHeightsBasedOnFont(Graphics g, ref int textAreaHeight)
    Parameters
    Type Name Description
    System.Drawing.Graphics g

    A System.Drawing.Graphics object.

    System.Int32 textAreaHeight

    A reference variable through which to return the height for the text area.

    Remarks

    Make sure to call the base class when you override this method.

    This method expects you to return a height for the text area through the reference variable, set the height of this control (if not in ComboBoxStyle.Simple mode) and the height of the drop-down button (DropDownButtonHeight).

    Dispose(Boolean)

    Declaration
    protected override void Dispose(bool disposing)
    Parameters
    Type Name Description
    System.Boolean disposing

    DrawBorderAndBackground(Graphics, Rectangle)

    Draws the border and background of the control.

    Declaration
    protected virtual void DrawBorderAndBackground(Graphics g, Rectangle rect)
    Parameters
    Type Name Description
    System.Drawing.Graphics g

    The System.Drawing.Graphics context.

    System.Drawing.Rectangle rect

    The System.Drawing.Rectangle within which to draw.

    Remarks

    This method is used to draw the border around the text area (when called from DrawEditPortionBorderAndBackground(PaintEventArgs) method) and around the list box area (when in ComboBoxStyle.Simple mode and called from the DrawListPortion(PaintEventArgs) method).

    This method uses themes to draw if necessary or calls DrawUnThemedBackground(Graphics, Rectangle) and DrawUnThemedBorder(Graphics, Rectangle) to draw the background and border.

    DrawDropDownPortion(PaintEventArgs)

    Called from the Paint event handler to draw the drop-down button.

    Declaration
    protected virtual void DrawDropDownPortion(PaintEventArgs e)
    Parameters
    Type Name Description
    System.Windows.Forms.PaintEventArgs e

    The System.Windows.Forms.PaintEventArgs from the Paint event.

    DrawEditPortion(PaintEventArgs)

    Called from the Paint event handler to draw the text portion.

    Declaration
    protected virtual void DrawEditPortion(PaintEventArgs e)
    Parameters
    Type Name Description
    System.Windows.Forms.PaintEventArgs e

    The System.Windows.Forms.PaintEventArgs from the Paint event.

    Remarks

    This method calls the DrawListModeEditPortion(PaintEventArgs, Color, Color, Boolean) method to draw the edit portion only when in ComboBoxStyle.DropDownList mode or when in design-mode.

    DrawEditPortionBorderAndBackground(PaintEventArgs)

    Called from the Paint event handler to draw the edit portion's border and background.

    Declaration
    protected virtual void DrawEditPortionBorderAndBackground(PaintEventArgs e)
    Parameters
    Type Name Description
    System.Windows.Forms.PaintEventArgs e

    The System.Windows.Forms.PaintEventArgs from the Paint event.

    Remarks

    This method calls the DrawBorderAndBackground(Graphics, Rectangle) method with the appropriate dimension to draw the border around the text portion.

    DrawListModeEditPortion(PaintEventArgs, Color, Color, Boolean)

    Called from DrawEditPortion(PaintEventArgs) to draw the text area when in ComboBoxStyle.DropDownList mode.

    Declaration
    protected virtual void DrawListModeEditPortion(PaintEventArgs e, Color highlightBG, Color highlightText, bool drawFocusRect)
    Parameters
    Type Name Description
    System.Windows.Forms.PaintEventArgs e

    The System.Windows.Forms.PaintEventArgs from the Paint event.

    System.Drawing.Color highlightBG

    The background color for the highlight.

    System.Drawing.Color highlightText

    The text color for the highlight.

    System.Boolean drawFocusRect

    Indicates whether to draw a focus rectangle.

    DrawListPortion(PaintEventArgs)

    Called from the Paint event handler to draw the list portion.

    Declaration
    protected virtual void DrawListPortion(PaintEventArgs e)
    Parameters
    Type Name Description
    System.Windows.Forms.PaintEventArgs e

    The System.Windows.Forms.PaintEventArgs from the Paint event.

    Remarks

    This method draws the list portion when in ComboBoxStyle.Simple mode.

    DrawUnThemedBackground(Graphics, Rectangle)

    Draws the unthemed background of this control.

    Declaration
    protected virtual void DrawUnThemedBackground(Graphics g, Rectangle rect)
    Parameters
    Type Name Description
    System.Drawing.Graphics g

    The System.Drawing.Graphics context.

    System.Drawing.Rectangle rect

    The System.Drawing.Rectangle within which to draw.

    Remarks

    Called by DrawBorderAndBackground(Graphics, Rectangle) to draw the background when not in themes mode.

    DrawUnThemedBorder(Graphics, Rectangle)

    Draws the unthemed border of this control.

    Declaration
    protected virtual void DrawUnThemedBorder(Graphics g, Rectangle rect)
    Parameters
    Type Name Description
    System.Drawing.Graphics g

    The System.Drawing.Graphics context.

    System.Drawing.Rectangle rect

    The System.Drawing.Rectangle within which to draw.

    Remarks

    Called by DrawBorderAndBackground(Graphics, Rectangle) to draw the border when not in themes mode.

    FindItem(String, Boolean, Int32, Boolean)

    Declaration
    protected virtual int FindItem(string prefix, bool select, int start, bool ignoreCase)
    Parameters
    Type Name Description
    System.String prefix
    System.Boolean select
    System.Int32 start
    System.Boolean ignoreCase
    Returns
    Type Description
    System.Int32

    ForwardKeyMessageToPopupControl(Int32, IntPtr, IntPtr)

    Forwards the key message to the attached PopupControl.

    Declaration
    protected virtual void ForwardKeyMessageToPopupControl(int msg, IntPtr wparam, IntPtr lparam)
    Parameters
    Type Name Description
    System.Int32 msg

    The message id.

    System.IntPtr wparam

    The first message parameter.

    System.IntPtr lparam

    The second message parameter.

    GetComboBoxDropDownWidth()

    Returns the width for the combo box drop-down button.

    Declaration
    protected virtual int GetComboBoxDropDownWidth()
    Returns
    Type Description
    System.Int32

    The button width.

    GetEmbeddedChildBounds()

    The bounds for the control that is associated with this popup when in DropDownStyle.Simple mode.

    Declaration
    protected virtual Rectangle GetEmbeddedChildBounds()
    Returns
    Type Description
    System.Drawing.Rectangle

    The bounds for the embedded control.

    GetEmbeddedChildBounds(Int32)

    Overloaded. The bounds for the control that is associated with this popup when in DropDownStyle.Simple mode.

    Declaration
    protected virtual Rectangle GetEmbeddedChildBounds(int comboHeight)
    Parameters
    Type Name Description
    System.Int32 comboHeight

    The height of the combo control.

    Returns
    Type Description
    System.Drawing.Rectangle

    The bounds for the embedded control.

    GetOfficeStyleComboBoxDropDownWidth()

    Returns the width for the combo box drop-down button when office style is on.

    Declaration
    protected virtual int GetOfficeStyleComboBoxDropDownWidth()
    Returns
    Type Description
    System.Int32

    The button width.

    GetPopupControlItemText(Int32)

    Declaration
    protected virtual string GetPopupControlItemText(int index)
    Parameters
    Type Name Description
    System.Int32 index
    Returns
    Type Description
    System.String

    GetPopupText()

    Declaration
    protected virtual string GetPopupText()
    Returns
    Type Description
    System.String

    HasListInterface()

    Declaration
    protected virtual bool HasListInterface()
    Returns
    Type Description
    System.Boolean

    HidePopup()

    Hides the drop-down list box.

    Declaration
    protected virtual void HidePopup()

    InitDropDownButton(DropDownButton)

    Called to initialize the DropDownButton used in the drop-down button portion of the combo.

    Declaration
    protected virtual void InitDropDownButton(DropDownButton ddButton)
    Parameters
    Type Name Description
    DropDownButton ddButton
    Remarks

    This method is called once to initialize the DropDownButton used to draw the drop-down portion of the combo.

    Make sure to call the base class when you override this method for default initialization.

    CreateDropDownButton()

    InitPopupContainer()

    Called to initialize the drop-down container.

    Declaration
    protected virtual void InitPopupContainer()
    Remarks

    This method is called once to initialize the drop-down container that hosts the drop-down list. Use the PopupContainer property to get a reference to the PopupControlContainer from inside an override of this method.

    Make sure to call the base class when you override this method for default initialization.

    CreatePopupContainer()

    InitScrollersFrame()

    Inits the scrollers frame.

    Declaration
    protected virtual void InitScrollersFrame()

    InitTextBox()

    Called to initialize the System.Windows.Forms.TextBox used in the editable text portion.

    Declaration
    protected virtual void InitTextBox()
    Remarks

    This method is called once to initialize the text box used to draw the editable portion of the combo. Use the TextBox property to get a reference to the text box from inside a override of this method.

    Make sure to call the base class when you override this method for default initialization.

    CreateTextBox()

    IsInputChar(Char)

    Declaration
    protected override bool IsInputChar(char charCode)
    Parameters
    Type Name Description
    System.Char charCode
    Returns
    Type Description
    System.Boolean

    IsInputKey(Keys)

    Declaration
    protected override bool IsInputKey(Keys keyData)
    Parameters
    Type Name Description
    System.Windows.Forms.Keys keyData
    Returns
    Type Description
    System.Boolean

    IsTextValid(String)

    Declaration
    protected virtual bool IsTextValid(string text)
    Parameters
    Type Name Description
    System.String text
    Returns
    Type Description
    System.Boolean

    IsValidIndex(Int32)

    Declaration
    protected virtual bool IsValidIndex(int index)
    Parameters
    Type Name Description
    System.Int32 index
    Returns
    Type Description
    System.Boolean

    MoveSelelctionInPopupControl(Boolean)

    Moves the current selection in the attached PopupControl.

    Declaration
    protected virtual void MoveSelelctionInPopupControl(bool up)
    Parameters
    Type Name Description
    System.Boolean up

    Indicates whether to move up.

    OnBeforePopup()

    Called before the popup gets dropped down.

    Declaration
    protected virtual void OnBeforePopup()

    OnBeginInit()

    Declaration
    protected virtual void OnBeginInit()

    OnBorder3DStyleChanged(EventArgs)

    Raises the Border3DStyleChanged event.

    Declaration
    protected virtual void OnBorder3DStyleChanged(EventArgs e)
    Parameters
    Type Name Description
    System.EventArgs e

    An EventArgs that contains the event data.

    Remarks

    Raising an event invokes the event handler through a delegate. For more information, see Raising an Event.

    The OnBorder3DStyleChanged method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.

    Note to Inheritors: When overriding OnBorder3DStyleChanged in a derived class, be sure to call the base class's OnBorder3DStyleChanged method so that registered delegates receive the event.

    OnBorderSidesChanged(EventArgs)

    Raises the BorderSidesChanged event.

    Declaration
    protected virtual void OnBorderSidesChanged(EventArgs e)
    Parameters
    Type Name Description
    System.EventArgs e

    An EventArgs that contains the event data.

    Remarks

    Raising an event invokes the event handler through a delegate. For more information, see Raising an Event.

    The OnBorderSidesChanged method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.

    Note to Inheritors: When overriding OmBorderSidesChanged in a derived class, be sure to call the base class's OnBorderSidesChanged method so that registered delegates receive the event.

    OnDropDown(EventArgs)

    Raises the Drop-Down event.

    Declaration
    protected virtual void OnDropDown(EventArgs e)
    Parameters
    Type Name Description
    System.EventArgs e

    An EventArgs that contains the event data.

    Remarks

    Raising an event invokes the event handler through a delegate. For more information, see Raising an Event.

    The OnDropDown method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.

    Note to Inheritors: When overriding OnDropDown in a derived class, be sure to call the base class's OnDropDown method so that registered delegates receive the event.

    OnDropDownStyleChanged(EventArgs)

    Raises the DropDownStyleChanged event.

    Declaration
    protected virtual void OnDropDownStyleChanged(EventArgs e)
    Parameters
    Type Name Description
    System.EventArgs e

    An EventArgs that contains the event data.

    Remarks

    Raising an event invokes the event handler through a delegate. For more information, see "Raising an Event".

    The DropDownStyleChanged method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.

    Note to Inheritors: When overriding OnDropDownStyleChanged in a derived class, be sure to call the base class's OnDropDownStyleChanged method so that registered delegates receive the event.

    OnEnabledChanged(EventArgs)

    Declaration
    protected override void OnEnabledChanged(EventArgs e)
    Parameters
    Type Name Description
    System.EventArgs e

    OnEndInit()

    Declaration
    protected virtual void OnEndInit()

    OnEnter(EventArgs)

    Declaration
    protected override void OnEnter(EventArgs e)
    Parameters
    Type Name Description
    System.EventArgs e

    OnFontChanged(EventArgs)

    Font chnaged

    Declaration
    protected override void OnFontChanged(EventArgs e)
    Parameters
    Type Name Description
    System.EventArgs e

    OnGotFocus(EventArgs)

    Declaration
    protected override void OnGotFocus(EventArgs e)
    Parameters
    Type Name Description
    System.EventArgs e

    OnHandleCreated(EventArgs)

    Declaration
    protected override void OnHandleCreated(EventArgs e)
    Parameters
    Type Name Description
    System.EventArgs e

    OnHandleDestroyed(EventArgs)

    Declaration
    protected override void OnHandleDestroyed(EventArgs e)
    Parameters
    Type Name Description
    System.EventArgs e

    OnKeyDown(KeyEventArgs)

    Declaration
    protected override void OnKeyDown(KeyEventArgs e)
    Parameters
    Type Name Description
    System.Windows.Forms.KeyEventArgs e

    OnKeyPress(KeyPressEventArgs)

    Declaration
    protected override void OnKeyPress(KeyPressEventArgs e)
    Parameters
    Type Name Description
    System.Windows.Forms.KeyPressEventArgs e

    OnLayout(LayoutEventArgs)

    Declaration
    protected override void OnLayout(LayoutEventArgs levent)
    Parameters
    Type Name Description
    System.Windows.Forms.LayoutEventArgs levent

    OnLostFocus(EventArgs)

    Declaration
    protected override void OnLostFocus(EventArgs e)
    Parameters
    Type Name Description
    System.EventArgs e

    OnMouseDown(MouseEventArgs)

    Declaration
    protected override void OnMouseDown(MouseEventArgs e)
    Parameters
    Type Name Description
    System.Windows.Forms.MouseEventArgs e

    OnMouseEnter(EventArgs)

    Declaration
    protected override void OnMouseEnter(EventArgs e)
    Parameters
    Type Name Description
    System.EventArgs e

    OnMouseLeave(EventArgs)

    Declaration
    protected override void OnMouseLeave(EventArgs e)
    Parameters
    Type Name Description
    System.EventArgs e

    OnMouseMove(MouseEventArgs)

    Declaration
    protected override void OnMouseMove(MouseEventArgs e)
    Parameters
    Type Name Description
    System.Windows.Forms.MouseEventArgs e

    OnMouseUp(MouseEventArgs)

    Declaration
    protected override void OnMouseUp(MouseEventArgs e)
    Parameters
    Type Name Description
    System.Windows.Forms.MouseEventArgs e

    OnMouseUpOnQuickSelect()

    Declaration
    protected virtual void OnMouseUpOnQuickSelect()

    OnMouseWheel(MouseEventArgs)

    Declaration
    protected override void OnMouseWheel(MouseEventArgs e)
    Parameters
    Type Name Description
    System.Windows.Forms.MouseEventArgs e

    OnNewListItemKeyedIn(Int32)

    Declaration
    protected virtual bool OnNewListItemKeyedIn(int indexFound)
    Parameters
    Type Name Description
    System.Int32 indexFound
    Returns
    Type Description
    System.Boolean

    OnNoChangeDetectedOnPopupClosed()

    Declaration
    protected virtual void OnNoChangeDetectedOnPopupClosed()

    OnPaint(PaintEventArgs)

    Declaration
    protected override void OnPaint(PaintEventArgs e)
    Parameters
    Type Name Description
    System.Windows.Forms.PaintEventArgs e

    OnPopupClosed(PopupClosedEventArgs)

    Called when the popup is closed.

    Declaration
    protected virtual void OnPopupClosed(PopupClosedEventArgs e)
    Parameters
    Type Name Description
    PopupClosedEventArgs e

    OnReadOnlyChanged(EventArgs)

    Raises the ReadOnlyChanged event.

    Declaration
    protected virtual void OnReadOnlyChanged(EventArgs e)
    Parameters
    Type Name Description
    System.EventArgs e

    An EventArgs that contains the event data.

    Remarks

    Raising an event invokes the event handler through a delegate. For more information, see "Raising an Event".

    The ReadOnlyChanged method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.

    Note to Inheritors: When overriding OnReadOnlyChanged in a derived class, be sure to call the base class's OnReadOnlyChanged method so that registered delegates receive the event.

    OnSelectionChangeCommitted(EventArgs)

    Raises the SelectionChangeCommitted event.

    Declaration
    protected virtual void OnSelectionChangeCommitted(EventArgs e)
    Parameters
    Type Name Description
    System.EventArgs e

    An EventArgs that contains the event data.

    Remarks

    Raising an event invokes the event handler through a delegate. For more information, see Raising an Event.

    The OnSelectionChangeCommitted method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.

    Note to Inheritors: When overriding OnSelectionChangeCommitted in a derived class, be sure to call the base class's OnSelectionChangeCommitted method so that registered delegates receive the event.

    OnSelectionChangedOnPopupClose()

    Declaration
    protected virtual void OnSelectionChangedOnPopupClose()

    OnSizeChanged(EventArgs)

    Declaration
    protected override void OnSizeChanged(EventArgs e)
    Parameters
    Type Name Description
    System.EventArgs e

    OnSystemColorsChanged(EventArgs)

    Overridden. See System.Windows.Forms.Control.OnSystemColorsChanged(System.EventArgs).

    Declaration
    protected override void OnSystemColorsChanged(EventArgs e)
    Parameters
    Type Name Description
    System.EventArgs e

    OnTabStopChanged(EventArgs)

    Declaration
    protected override void OnTabStopChanged(EventArgs e)
    Parameters
    Type Name Description
    System.EventArgs e

    OnTextBoxKeyUp(KeyEventArgs)

    Declaration
    protected virtual void OnTextBoxKeyUp(KeyEventArgs e)
    Parameters
    Type Name Description
    System.Windows.Forms.KeyEventArgs e

    OnThemeChanged(EventArgs)

    Raises the ThemeChanged event.

    Declaration
    protected virtual void OnThemeChanged(EventArgs e)
    Parameters
    Type Name Description
    System.EventArgs e

    An EventArgs that contains the event data.

    Remarks

    The OnThemeChanged method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.

    Note to Inheritors: When overriding OnThemeChanged in a derived class, be sure to call the base class's OnThemeChanged method so that registered delegates receive the event.

    OnValidated(EventArgs)

    Declaration
    protected override void OnValidated(EventArgs e)
    Parameters
    Type Name Description
    System.EventArgs e

    OtherChangesMade()

    Indicates whether another change was made except text changing in control.

    Declaration
    protected virtual bool OtherChangesMade()
    Returns
    Type Description
    System.Boolean

    True if changes were detected; false otherwise.

    PerformAllowNewText(Message)

    Verifies whether new text is allowed to be entered from native message.

    Declaration
    public virtual bool PerformAllowNewText(Message m)
    Parameters
    Type Name Description
    System.Windows.Forms.Message m

    The message.

    Returns
    Type Description
    System.Boolean

    True if the message is handled.

    PerformTextAutoComplete(KeyPressEventArgs)

    Performs auto complete in the text area.

    Declaration
    protected virtual void PerformTextAutoComplete(KeyPressEventArgs e)
    Parameters
    Type Name Description
    System.Windows.Forms.KeyPressEventArgs e

    The arguments of the KeyPress event.

    ProcessCmdKey(ref Message, Keys)

    Declaration
    protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
    Parameters
    Type Name Description
    System.Windows.Forms.Message msg
    System.Windows.Forms.Keys keyData
    Returns
    Type Description
    System.Boolean

    ProcessDDMouseDown()

    Declaration
    protected virtual void ProcessDDMouseDown()

    ProcessDDMouseDown(MouseEventArgs)

    Declaration
    protected virtual void ProcessDDMouseDown(MouseEventArgs e)
    Parameters
    Type Name Description
    System.Windows.Forms.MouseEventArgs e

    ProcessDialogKey(Keys)

    Declaration
    protected override bool ProcessDialogKey(Keys keyData)
    Parameters
    Type Name Description
    System.Windows.Forms.Keys keyData
    Returns
    Type Description
    System.Boolean

    ProcessMouseMove(MouseEventArgs, Boolean)

    Processes mouse moves on the combo-box and textbox area.

    Declaration
    protected virtual void ProcessMouseMove(MouseEventArgs e, bool fromTextBox)
    Parameters
    Type Name Description
    System.Windows.Forms.MouseEventArgs e

    The event args of the MouseMove event.

    System.Boolean fromTextBox

    Indicates whether this was called due to mouse move in the text area or combo.

    ProcessPopupControlMouseMove(Object, MouseEventArgs)

    Declaration
    protected virtual void ProcessPopupControlMouseMove(object sender, MouseEventArgs e)
    Parameters
    Type Name Description
    System.Object sender
    System.Windows.Forms.MouseEventArgs e

    RaiseSelectionChangeCommitted()

    Raises the SelectionChangeCommitted event.

    Declaration
    public void RaiseSelectionChangeCommitted()
    Remarks

    The event will be fired usually when the user commits selection change. You could use this method to raise an event manually for a custom scenario.

    ResetBackColor()

    Resets the System.Windows.Forms.Control.BackColor property to its default value.

    Declaration
    public override void ResetBackColor()

    ResetDropDownWidth()

    Resets the DropDownWidth property's value to its default.

    Declaration
    public void ResetDropDownWidth()

    ResetFlatBorderColor()

    Declaration
    protected void ResetFlatBorderColor()

    ResetToLatestCommittedText()

    Declaration
    protected virtual void ResetToLatestCommittedText()

    SetBoundsCore(Int32, Int32, Int32, Int32, BoundsSpecified)

    Declaration
    protected override void SetBoundsCore(int x, int y, int width, int height, BoundsSpecified specified)
    Parameters
    Type Name Description
    System.Int32 x
    System.Int32 y
    System.Int32 width
    System.Int32 height
    System.Windows.Forms.BoundsSpecified specified

    SetNeedLayout(Boolean)

    Forces laying out of the combo elements within the next Paint Message handler.

    Declaration
    protected virtual void SetNeedLayout(bool needLayout)
    Parameters
    Type Name Description
    System.Boolean needLayout

    True to force; False to prevent layout.

    SetPopupText(String)

    Declaration
    protected virtual void SetPopupText(string value)
    Parameters
    Type Name Description
    System.String value

    SetSelectedText(String, Int32)

    Declaration
    protected virtual void SetSelectedText(string text, int foundIndex)
    Parameters
    Type Name Description
    System.String text
    System.Int32 foundIndex

    SetText(String, Boolean)

    Declaration
    protected virtual void SetText(string newValue, bool fireChangeEvent)
    Parameters
    Type Name Description
    System.String newValue
    System.Boolean fireChangeEvent

    SetTextBoxBounds(Rectangle)

    Declaration
    protected virtual void SetTextBoxBounds(Rectangle rect)
    Parameters
    Type Name Description
    System.Drawing.Rectangle rect

    ShouldSerializeBackColor()

    Declaration
    protected bool ShouldSerializeBackColor()
    Returns
    Type Description
    System.Boolean

    ShouldSerializeDropDownWidth()

    Indicates whether the DropDownWidth property's value is the default.

    Declaration
    public bool ShouldSerializeDropDownWidth()
    Returns
    Type Description
    System.Boolean

    True if the value is not the default; false otherwise.

    ShouldSerializeFlatBorderColor()

    Declaration
    protected bool ShouldSerializeFlatBorderColor()
    Returns
    Type Description
    System.Boolean

    ShowPopup()

    Shows the drop-down.

    Declaration
    protected virtual void ShowPopup()

    UnInitTextBox()

    Declaration
    protected virtual void UnInitTextBox()

    UpdateDropDownButtonBounds()

    Updates the bounds of the drop-down button bounds.

    Declaration
    protected virtual void UpdateDropDownButtonBounds()
    Remarks

    Sets the bounds based on the value returned by the GetComboBoxDropDownWidth() method.

    UpdateEditPortionBounds(Int32)

    Updates the internal textbox's bounds and visibility based on the DropDownStyle.

    Declaration
    protected virtual void UpdateEditPortionBounds(int textAreaHeight)
    Parameters
    Type Name Description
    System.Int32 textAreaHeight

    The height of the text area.

    UpdateLayout(Graphics)

    Declaration
    public void UpdateLayout(Graphics g)
    Parameters
    Type Name Description
    System.Drawing.Graphics g

    UpdatePopupBounds()

    Declaration
    protected virtual void UpdatePopupBounds()

    UpdatePopupControl()

    Updates the attached popup control based on the current Text property.

    Declaration
    public virtual void UpdatePopupControl()
    Remarks

    Call this method to update the popup list box, for example, with the latest text value that the user might have entered. This is useful when you enable auto completion in the text area and force the list box's SelectedValue to be updated to the latest text value in this control's Validated event.

    UpdatePopupControlBounds()

    Updates the attached PopupControl's bounds.

    Declaration
    protected virtual void UpdatePopupControlBounds()
    Remarks

    The base class updates the PopupControl's bounds and visibility based on the DropDownStyle settings.

    UpdatePopupControlRelationship()

    Updates the attached PopupControl's parent-child relationship.

    Declaration
    protected virtual void UpdatePopupControlRelationship()
    Remarks

    If in ComboBoxStyle.Simple mode, the base class implementation parents the Popup Control to the combo itself. Otherwise, it parents the PopupContainer to the Popup Control.

    UpdateText(Boolean)

    Updates the Text property based on the PopupControl's selected value.

    Declaration
    public virtual bool UpdateText(bool fireEvent)
    Parameters
    Type Name Description
    System.Boolean fireEvent

    Indicates whether the SelectionChangeCommitted event should be fired if the text is changed.

    Returns
    Type Description
    System.Boolean

    True if the SelectionChangeCommitted event was fired; False otherwise.

    Remarks

    You normally do not have to call this method. However when you programmatically update the SelectedValue of a plug in the list control, you might have to call this method to update the combo's text based on that new value.

    WndProc(ref Message)

    Declaration
    protected override void WndProc(ref Message m)
    Parameters
    Type Name Description
    System.Windows.Forms.Message m

    Events

    Border3DStyleChanged

    Occurs when border's 3D style is changed.

    Declaration
    public event EventHandler Border3DStyleChanged
    Event Type
    Type Description
    System.EventHandler

    BorderSidesChanged

    Fired when BorderSides are changed.

    Declaration
    public event EventHandler BorderSidesChanged
    Event Type
    Type Description
    System.EventHandler

    DropDown

    Occurs before the drop-down portion is shown.

    Declaration
    public event EventHandler DropDown
    Event Type
    Type Description
    System.EventHandler

    DropDownStyleChanged

    Occurs when the DropDownStyle of the combo changes.

    Declaration
    public event EventHandler DropDownStyleChanged
    Event Type
    Type Description
    System.EventHandler

    ReadOnlyChanged

    Occurs when the ReadOnly property of the combo changes.

    Declaration
    public event EventHandler ReadOnlyChanged
    Event Type
    Type Description
    System.EventHandler

    SelectionChangeCommitted

    Occurs when the user selects a new text for the combo in one of many possible ways.

    Declaration
    public event EventHandler SelectionChangeCommitted
    Event Type
    Type Description
    System.EventHandler
    Remarks

    This event will be fired for the following cases:

    • When the user selects a new item in the list box by clicking or pressing Enter.
    • When the user Tabs out of the combo after changing the current text and Validation was successful.

    ThemeChanged

    Fired when the ThemesEnabled property changes.

    Declaration
    public event EventHandler ThemeChanged
    Event Type
    Type Description
    System.EventHandler

    Explicit Interface Implementations

    INonClientPaintingSupport.NonClientPaint(PaintEventArgs, Rectangle, Rectangle)

    Declaration
    IntPtr INonClientPaintingSupport.NonClientPaint(PaintEventArgs e, Rectangle displayRect, Rectangle windowRectInScreen)
    Parameters
    Type Name Description
    System.Windows.Forms.PaintEventArgs e
    System.Drawing.Rectangle displayRect
    System.Drawing.Rectangle windowRectInScreen
    Returns
    Type Description
    System.IntPtr

    ISupportOffice2007Theme.EnableOffice2007Style()

    Declaration
    void ISupportOffice2007Theme.EnableOffice2007Style()

    IThemedControl.ThemesEnabled

    Indicates whether themes are enabled for this control.

    Declaration
    bool IThemedControl.ThemesEnabled { get; set; }
    Returns
    Type Description
    System.Boolean

    IVisualStyle.VisualTheme

    Declaration
    string IVisualStyle.VisualTheme { get; set; }
    Returns
    Type Description
    System.String

    Implements

    IThemedControl
    System.ComponentModel.ISupportInitialize
    INonClientPaintingSupport
    ISupportOffice2007Theme
    IVisualStyle
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