Class DropDownListModel<TValue, TItem>

Represents configuration and events for the Syncfusion DropDownList component, including data-binding, filtering, popup management, and display customization.

Inheritance

System.Object

DropDownListModel<TValue, TItem>

Namespace: Syncfusion.Blazor.DropDowns

Assembly: Syncfusion.Blazor.dll

Syntax

public class DropDownListModel<TValue, TItem> : Object

Type Parameters

Name	Description
TValue	Specifies the type of DropDownListModel.
TItem	Specifies the typr of value.

Remarks

Use the properties and event callbacks in DropDownListModel to manage all aspects of the DropDownList’s data, appearance, and user interaction patterns.

Examples

<SfDropDownList TValue="string" TItem="DropItem" DataSource="@items" Placeholder="Choose an item">
    <DropDownListEvents TValue="string" TItem="DropItem" Change="OnChangeHandler" />
</SfDropDownList>

Constructors

DropDownListModel()

Declaration

public DropDownListModel()

Properties

ActionBegin

Event data when remote data fetching is initiated for this DropDownList.

Declaration

public ActionBeginEventArgs ActionBegin { get; set; }

Property Value

Type	Description
ActionBeginEventArgs	An ActionBeginEventArgs instance for fetch initiation.

ActionComplete

Event data for when remote data fetching is complete.

Declaration

public ActionCompleteEventArgs ActionComplete { get; set; }

Property Value

Type	Description
ActionCompleteEventArgs	An ActionCompleteEventArgs object containing completion metadata.

ActionFailure

Callback for errors or fail scenarios when fetching data from remote sources.

Declaration

public EventCallback<object> ActionFailure { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<System.Object>	The EventCallback<object> for handling data fetch failures.

ActionFailureTemplate

Template displayed on failure to fetch remote data for the popup list.

Declaration

public RenderFragment ActionFailureTemplate { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.RenderFragment	Set as a Microsoft.AspNetCore.Components.RenderFragment.

AllowFiltering

Controls whether to show the search box/filter bar.

Declaration

public bool AllowFiltering { get; set; }

Property Value

Type	Description
System.Boolean	true to show the search box. false (default) hides it.

Remarks

Requires AllowFiltering to be set. Triggers Filtering event as users type.

BeforeOpen

Arguments raised immediately before the popup opens.

Declaration

public BeforeOpenEventArgs BeforeOpen { get; set; }

Property Value

Type	Description
BeforeOpenEventArgs	A BeforeOpenEventArgs instance with relevant data.

Blur

Callback triggered when input focus moves out of the DropDownList.

Declaration

public EventCallback<object> Blur { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<System.Object>	Use EventCallback<object> to handle blur/validation logic.

Change

Callback when a DropDownList item is selected or value changes via user interaction.

Declaration

public EventCallback<object> Change { get; set; }

Property Value

Type
Microsoft.AspNetCore.Components.EventCallback<System.Object>

Remarks

Use this for cascading lists, custom value change reactions, or analytics.

Examples

@code { void OnChangeHandler(object args) {/*...*/} }

Close

Callback after the popup closes.

Declaration

public EventCallback<object> Close { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<System.Object>	EventCallback<object> used to reset state, run analytics, or trigger UI logic after popup dismissal.

Created

Callback after the component is initialized and created.

Declaration

public EventCallback<object> Created { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<System.Object>	This event is useful for executing post-initialization logic or startup configuration.

CssClass

Custom CSS class(es) added to the DropDownList root element for styling.

Declaration

public string CssClass { get; set; }

Property Value

Type	Description
System.String	Class names as string. null by default.

DataBound

Arguments provided when binding data to DropDownList completes.

Declaration

public DataBoundEventArgs DataBound { get; set; }

Property Value

Type	Description
DataBoundEventArgs	A DataBoundEventArgs instance with completion info.

DataSource

Collection of items or a data manager instance to bind to the DropDownList.

Declaration

public IEnumerable<TItem> DataSource { get; set; }

Property Value

Type
System.Collections.Generic.IEnumerable<TItem>

Remarks

Ignored from serialization.

DebounceDelay

Milliseconds to wait after user types before filtering/search logic starts. Applies with AllowFiltering.

Declaration

public int DebounceDelay { get; set; }

Property Value

Type	Description
System.Int32	int value. Default is 300.

Destroyed

Callback when the DropDownList is destroyed/disposed.

Declaration

public EventCallback<object> Destroyed { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<System.Object>	Use for code cleanup or reporting unmount/teardown.

Enabled

Sets whether user interaction is enabled or disabled for this DropDownList.

Declaration

public bool Enabled { get; set; }

Property Value

Type	Description
System.Boolean	true (default) for enabled. false disables all interaction.

EnableRtl

Enable right-to-left (RTL) rendering of DropDownList (used in RTL locales).

Declaration

public bool EnableRtl { get; set; }

Property Value

Type	Description
System.Boolean	true enables RTL. Default is false.

EnableVirtualization

Enable virtual scrolling for large-data DropDownList performance (fetch on scroll, partial view, etc).

Declaration

public bool EnableVirtualization { get; set; }

Property Value

Type	Description
System.Boolean	true enables partial-view fetch; false disables.

Remarks

Highly recommended for lists exceeding 1000 items.

FilterBarPlaceholder

Placeholder watermarked text shown in the filter bar (search box), if visible.

Declaration

public string FilterBarPlaceholder { get; set; }

Property Value

Type	Description
System.String	String specifying search placeholder. null for no placeholder.

Filtering

Callback triggered during filter bar text input if AllowFiltering is enabled.

Declaration

public EventCallback<object> Filtering { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<System.Object>	Bind custom filtering, search, or logics with EventCallback<object>.

FilterType

Specifies the filter search type: StartsWith, Contains, etc.

Declaration

public FilterType FilterType { get; set; }

Property Value

Type	Description
FilterType	A FilterType enum value.

FloatLabelType

Controls floating label UI behavior for placeholder text.

Declaration

public FloatLabelType FloatLabelType { get; set; }

Property Value

Type	Description
FloatLabelType	Never, Always, or Auto. Default: Never.

Focus

Callback when the DropDownList receives focus.

Declaration

public EventCallback<object> Focus { get; set; }

Property Value

Type
Microsoft.AspNetCore.Components.EventCallback<System.Object>

Remarks

Useful for accessibility, keyboard navigation, or showing hints.

FooterTemplate

Template for customizing the popup footer content.

Declaration

public RenderFragment FooterTemplate { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.RenderFragment	Set as a RenderFragment.

HeaderTemplate

Template for customizing the popup header content.

Declaration

public RenderFragment HeaderTemplate { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.RenderFragment	Set as a Microsoft.AspNetCore.Components.RenderFragment.

HtmlAttributes

Additional input HTML attributes set on the DropDownList root element.

Declaration

public object HtmlAttributes { get; set; }

Property Value

Type	Description
System.Object	Properties such as disabled or value.

Remarks

When both a property and attribute are set, the property’s value is used.

IgnoreAccent

If true, diacritics/accented character differences are ignored during search (default: false).

Declaration

public bool IgnoreAccent { get; set; }

Property Value

Type	Description
System.Boolean	true to ignore; false to match on accents.

IgnoreCase

If true, string searches ignore case (default: true).

Declaration

public bool IgnoreCase { get; set; }

Property Value

Type	Description
System.Boolean	true for case-insensitive; false to match case.

Index

Index of the currently selected list item. 0 for first item by default.

Declaration

public int Index { get; set; }

Property Value

Type	Description
System.Int32	Integer with the zero-based selected index.

Open

Callback when the popup opens on this DropDownList.

Declaration

public EventCallback<object> Open { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<System.Object>	Use for analytics or asynchronous UI preparations.

Placeholder

Placeholder hint or watermark text, shown until the user interacts or selects a value.

Declaration

public string Placeholder { get; set; }

Property Value

Type	Description
System.String	Hint or placeholder string.

Remarks

Displayed based on FloatLabelType setting.

PopupDisplayMode

Controls the display mode for the popup (e.g., FullScreen, etc).

Declaration

public PopupDisplayMode PopupDisplayMode { get; set; }

Property Value

Type	Description
PopupDisplayMode	A PopupDisplayMode value (default: FullScreen).

PopupHeight

Height of the suggestion popup (default: auto).

Declaration

public string PopupHeight { get; set; }

Property Value

Type	Description
System.String	Accepts any CSS length unit or auto.

PopupWidth

Width of the suggestion popup. By default, matches the DropDownList width.

Declaration

public string PopupWidth { get; set; }

Property Value

Type	Description
System.String	Accepts any CSS length unit.

Query

External query object used for customizing remote data and filtering.

Declaration

public Query Query { get; set; }

Property Value

Type	Description
Query	Custom query object or null.

Readonly

Determines if the DropDownList is in readonly mode.

Declaration

public bool Readonly { get; set; }

Property Value

Type	Description
System.Boolean	true to lock value. false (default) for normal operation.

Remarks

Readonly disables value changes without disabling component focus or keyboard navigation.

Select

Callback when an item is selected via mouse, tap, or keyboard.

Declaration

public EventCallback<object> Select { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<System.Object>	EventCallback<object> for item selection events.

ShowClearButton

If true, a clear button appears, which clears Value, Text, and Index.

Declaration

public bool ShowClearButton { get; set; }

Property Value

Type	Description
System.Boolean	Set to true for clear-button UI; false disables.

Text

Text to display in the input when an item is selected.

Declaration

public string Text { get; set; }

Property Value

Type	Description
System.String	Current selection’s display text.

Value

Value of the currently selected item.

Declaration

public TValue Value { get; set; }

Property Value

Type
TValue

ValueTemplate

Template for customizing how the selected value is presented in the DropDownList input.

Declaration

public RenderFragment<TValue> ValueTemplate { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.RenderFragment<TValue>	Set as a Microsoft.AspNetCore.Components.RenderFragment<>.

Width

Sets the width of this DropDownList (CSS px, %, rem, etc). Default: auto.

Declaration

public string Width { get; set; }

Property Value

Type	Description
System.String	Width string or null for auto.