Class ComboDropDown

Inheritance
System.Object
ComboDropDown
ComboBoxBase
Implements
System.ComponentModel.ISupportInitialize
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
System.Boolean

cachedBackColor

Cached BackColor of ComboBox.

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

cachedForeColor

Cached BackColor of ComboBox.

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

initializing

Declaration
protected bool initializing
Field Value
Type
System.Boolean

m_lastFoundIndex

Declaration
protected int m_lastFoundIndex
Field Value
Type
System.Int32

m_scrollersFrame

Declaration
protected ScrollersFrame m_scrollersFrame
Field Value
Type
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
System.Boolean

BackColor

Gets or sets the back color. (overridden property)

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

BackgroundImage

Specifies the BackgroundImage.(overridden property)

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

BackgroundImageLayout

Gets or sets background image layout.

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

BeforeTouchSize

Gets/Sets Control size before touch enabled

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

Border3DStyle

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

Declaration
public Border3DStyle Border3DStyle { get; set; }
Property Value
Type
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
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
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
ComboBoxAdvRenderer

ContextMenu

Gets or sets the ContextMenu. (overridden property)

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

CreateParams

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

DefaultSize

Declaration
protected override Size DefaultSize { get; }
Property Value
Type
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
DropDownButton

DropDownButtonHeight

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

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

Font

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

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

ForeColor

Gets or sets the ForeColor. (overridden property)

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

IgnorePopupValueChange

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

IsInitializing

Gets a value indicating whether this instance is initializing.

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

IsPopUpControlType

Check whether the ComboBox is ComboDropDown or ComboBoxAdv

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

LastCommittedText

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

MatchFirstCharacterOnly

This property defines the autocomplete behavior in DropDownList mode.

Declaration
public bool MatchFirstCharacterOnly { get; set; }
Property Value
Type
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
System.Drawing.Color

MetroColor

Gets or sets the metrocolor.

Declaration
public Color MetroColor { get; set; }
Property Value
Type
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
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
Office2007Theme

Office2010ColorTheme

Gets or sets office 2010 color theme.

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

PopupContainer

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

Declaration
public PopupControlContainer PopupContainer { get; }
Property Value
Type
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
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
System.Boolean

Text

Gets or sets the text associated with this control.

Declaration
public override string Text { get; set; }
Property Value
Type
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
System.Windows.Forms.TextBox

UseBackColor

Gets or sets a value to have effect of BackColor

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

UseMetroButtonColor

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

GetPopupText()

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

HasListInterface()

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

IsInputKey(Keys)

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

IsTextValid(String)

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

IsValidIndex(Int32)

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

BorderSidesChanged

Fired when BorderSides are changed.

Declaration
public event EventHandler BorderSidesChanged
Event Type
Type
System.EventHandler

DropDown

Occurs before the drop-down portion is shown.

Declaration
public event EventHandler DropDown
Event Type
Type
System.EventHandler

DropDownStyleChanged

Occurs when the DropDownStyle of the combo changes.

Declaration
public event EventHandler DropDownStyleChanged
Event Type
Type
System.EventHandler

ReadOnlyChanged

Occurs when the ReadOnly property of the combo changes.

Declaration
public event EventHandler ReadOnlyChanged
Event Type
Type
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
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
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
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
System.Boolean

IVisualStyle.VisualTheme

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

Implements

System.ComponentModel.ISupportInitialize