Class MultiSelectEvents<TValue, TItem>

Represents the event handlers for a MultiSelect Dropdown component.

Inheritance

System.Object

MultiSelectEvents<TValue, TItem>

Namespace: Syncfusion.Blazor.DropDowns

Assembly: Syncfusion.Blazor.dll

Syntax

public class MultiSelectEvents<TValue, TItem> : OwningComponentBase

Type Parameters

Name	Description
TValue	Specifies the value type.
TItem	Specifies the type of MultiSelectEvents.

Constructors

MultiSelectEvents()

Declaration

public MultiSelectEvents()

Properties

Blur

Gets or sets an event callback that is invoked when the MultiSelect Dropdown component loses focus.

Declaration

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

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<System.Object>	An EventCallback<object> that is called upon component blur.

Remarks

Use this event to perform operations when the MultiSelect loses focus, such as validation triggers or UI state changes.

ChipSelected

Gets or sets an event callback that is invoked when a chip is selected in the MultiSelect Dropdown component.

Declaration

public EventCallback<ChipSelectedEventArgs<TItem>> ChipSelected { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<ChipSelectedEventArgs<TItem>>	An EventCallback<ChipSelectedEventArgs<TItem>> that is called when a chip (token) is selected. The event provides ChipSelectedEventArgs<TItem> describing the selected chip data.

Remarks

Use this event to determine which chip has been selected by the user.

Examples

<SfMultiSelect TItem="string" TValue="string" DataSource="@MyList">
    <MultiSelectEvents TValue="string" TItem="string" ChipSelected="@OnChipSelected"/>
</SfMultiSelect>
@code {
    private List<string> MyList = new List<string>();
    public void OnChipSelected(ChipSelectedEventArgs<string> args) {
        // New chip value is args.ChipData
    }
}

Cleared

Gets or sets an event callback invoked after all items have been cleared using the clear icon in the MultiSelect Dropdown component.

Declaration

public EventCallback<MouseEventArgs> Cleared { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<Microsoft.AspNetCore.Components.Web.MouseEventArgs>	An EventCallback<MouseEventArgs> occurring upon invoking clear selection.

Remarks

Use this event for post-processing after all MultiSelect values are cleared.

Closed

Gets or sets an event callback invoked after the dropdown popup has been closed for the MultiSelect Dropdown component.

Declaration

public EventCallback<ClosedEventArgs> Closed { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<ClosedEventArgs>	An EventCallback<ClosedEventArgs> fired after the popup closes, providing ClosedEventArgs event details.

Remarks

Use this event to adjust related UI or perform operations post-close.

Created

Gets or sets an event callback invoked when the MultiSelect Dropdown component is created.

Declaration

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

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<System.Object>	An EventCallback<object> triggered once the component initialization is completed.

Remarks

Use this event for logic dependent on component creation or to access references.

CustomValueSpecifier

Gets or sets an event callback that is invoked when custom values, not present in the data source, are selected in the MultiSelect Dropdown component.

Declaration

public EventCallback<CustomValueEventArgs<TItem>> CustomValueSpecifier { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<CustomValueEventArgs<TItem>>	An EventCallback<CustomValueEventArgs<TItem>> triggered when a custom value is selected. Receives CustomValueEventArgs<TItem> for custom logic.

Remarks

Allows the component to handle values that are not in the provided data source.

Examples

<SfMultiSelect TValue="int" TItem="Countries" DataSource="@CountryList">
    <MultiSelectEvents TValue="int" TItem="Countries" CustomValueSpecifier="@customValue"/>
    <MultiSelectFieldSettings Text="Name" Value="Code"/>
</SfMultiSelect>
@code {
    private List<Countries> CountryList = new List<Countries>();
    public class Countries {
        public string Name { get; set; }
        public int Code { get; set; }
    }
    void customValue(CustomValueEventArgs<Countries> args) {
        args.NewData = new Countries() { Code = 103, Name = args.Text };
    }
}

DataBound

Gets or sets an event callback that is invoked after the data source is populated in the popup list for the MultiSelect Dropdown component.

Declaration

public EventCallback<DataBoundEventArgs> DataBound { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<DataBoundEventArgs>	An EventCallback<DataBoundEventArgs> called after the popup is populated.

Remarks

Use this event for post-processing or side-effects based on the data bound to the popup list.

Destroyed

Gets or sets an event callback invoked when the MultiSelect Dropdown component is destroyed.

Declaration

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

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<System.Object>	An EventCallback<object> triggered as the component is torn down.

Remarks

Use this event to perform cleanup tasks or unsubscribe from services.

Filtering

Gets or sets an event callback invoked whenever a character is typed in the MultiSelect Dropdown search box.

Declaration

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

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<FilteringEventArgs>	An EventCallback<FilteringEventArgs> fired on filter input. Provides the filtering arguments for query overrides.

Remarks

Prevent the default filter action and enable your own query by setting the FilteringEventArgs.PreventDefaultAction property. You can then pass a modified data source and query to FilterAsync(IEnumerable<TItem>, Query, FieldSettingsModel) method for custom filtering.

Examples

<SfMultiSelect @ref="MultiSelectObj" TItem="string" TValue="string" AllowFiltering="true" DataSource="@MyList">
    <MultiSelectEvents TValue="string" TItem="string" Filtering="@OnFilteringHandler" />
</SfMultiSelect>
@code {
    private SfMultiSelect<string, string> MultiSelectObj;
    private List<string> MyList = new List<string>();
    async Task OnFilteringHandler(FilteringEventArgs args) {
        args.PreventDefaultAction = true;
        var query = new Query().Where(new WhereFilter() { Field = "Text", Operator = "contains", value = args.Text, IgnoreCase = true });
        await MultiSelectObj.FilterAsync(MyList, query);
    }
}

Focus

Gets or sets an event callback invoked when the MultiSelect Dropdown component receives focus.

Declaration

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

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<System.Object>	An EventCallback<object> triggered upon focus.

Remarks

Use this event for validation, input guidance, or UI enhancement when the MultiSelect receives focus.

OnActionBegin

Gets or sets an event callback that is invoked before fetching data from the data source in the MultiSelect Dropdown component.

Declaration

public EventCallback<ActionBeginEventArgs> OnActionBegin { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<ActionBeginEventArgs>	An EventCallback<ActionBeginEventArgs> that is called before any data load operation begins. The event receives ActionBeginEventArgs with action context.

Remarks

Use the OnActionBegin event to perform custom logic or cancel the upcoming data operation.

Examples

<SfMultiSelect TItem="string" TValue="string" DataSource="@MyList">
    <MultiSelectEvents TValue="string" TItem="string" OnActionBegin="@OnActionBeginHandler"/>
</SfMultiSelect>
@code {
    private List<string> MyList = new List<string>();
    public void OnActionBeginHandler(ActionBeginEventArgs args) {
        // Custom logic
    }
}

OnActionComplete

Gets or sets an event callback that is invoked after data is fetched from the data source in the MultiSelect Dropdown component.

Declaration

public EventCallback<ActionCompleteEventArgs<TItem>> OnActionComplete { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<ActionCompleteEventArgs<TItem>>	An EventCallback<ActionCompleteEventArgs<TItem>> that is called after the data fetch operation has completed successfully. The event receives ActionCompleteEventArgs<TItem> with result information.

Remarks

Use the OnActionComplete event for post-processing on fetched data.

Examples

<SfMultiSelect TItem="string" TValue="string" DataSource="@MyList">
    <MultiSelectEvents TValue="string" TItem="string" OnActionComplete="@OnActionCompleteHandler"/>
</SfMultiSelect>
@code {
    private List<string> MyList = new List<string>();
    public void OnActionCompleteHandler(ActionCompleteEventArgs<string> args) {
        // Custom post-fetch logic
    }
}

OnActionFailure

Gets or sets an event callback that is invoked when the data fetch request fails for the MultiSelect Dropdown component.

Declaration

public EventCallback<Exception> OnActionFailure { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<System.Exception>	An EventCallback<Exception> that is called if the data fetch request fails.

Remarks

Use the OnActionFailure event to handle data retrieval errors for the MultiSelect Dropdown component.

Examples

<SfMultiSelect TItem="string" TValue="string" DataSource="@MyList">
    <MultiSelectEvents TValue="string" TItem="string" OnActionFailure="@OnFailureHandler"/>
</SfMultiSelect>
@code {
    private List<string> MyList = new List<string>();
    public void OnFailureHandler(Exception ex) {
        // Log error
    }
}

OnChipTag

Gets or sets an event callback invoked before the selected item is set as a chip in the MultiSelect Dropdown component.

Declaration

public EventCallback<TaggingEventArgs<TItem>> OnChipTag { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<TaggingEventArgs<TItem>>	An EventCallback<TaggingEventArgs<TItem>> called before chip tagging. Passes the item context for further customization.

Remarks

Use this event to modify the way items are displayed as chips on selection.

OnClose

Gets or sets an event callback that is invoked before the dropdown popup closes in the MultiSelect Dropdown component.

Declaration

public EventCallback<PopupEventArgs> OnClose { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<PopupEventArgs>	An EventCallback<PopupEventArgs> that is triggered before the popup is closed, receiving PopupEventArgs that allows cancellation of the popup closure.

Remarks

Prevent the dropdown popup close action using PopupEventArgs.Cancel. If cancelled, the popup remains open.

Examples

<SfMultiSelect TItem="string" TValue="string" DataSource="@MyList">
    <MultiSelectEvents TValue="string" TItem="string" OnClose="@OnCloseHandler"/>
</SfMultiSelect>
@code {
    private List<string> MyList = new List<string>();
    public void OnCloseHandler(PopupEventArgs args) {
        args.Cancel = true;
    }
}

OnOpen

Gets or sets an event callback invoked before the dropdown popup opens in the MultiSelect Dropdown component.

Declaration

public EventCallback<BeforeOpenEventArgs> OnOpen { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<BeforeOpenEventArgs>	An EventCallback<BeforeOpenEventArgs> that is triggered before the popup opens. The event receives BeforeOpenEventArgs.

Remarks

Prevent the popup open action using BeforeOpenEventArgs.Cancel property.

Examples

<SfMultiSelect TItem="string" TValue="string" DataSource="@MyList">
    <MultiSelectEvents TValue="string" TItem="string" OnOpen="@OnOpenHandler"/>
</SfMultiSelect>
@code {
    private List<string> MyList = new List<string>();
    public void OnOpenHandler(BeforeOpenEventArgs args) {
        args.Cancel = true;
    }
}

OnResizeStart

Gets or sets an event callback that is raised when the resizing action of the popup begins in the MultiSelect Dropdown component.

Declaration

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

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<System.Object>	An EventCallback<object> that receives an event argument object containing resize start data for the popup.

Remarks

Use the OnResizeStart event to perform custom actions when the user initiates resizing of the popup. This event can be useful for setting initial states, logging, or displaying messages when resizing starts.

Examples

<SfMultiSelect TValue="string[]" AllowResize="true">
    <MultiSelectEvents OnResizeStart="HandleResizeStart" />
</SfMultiSelect>
@code {
    private void HandleResizeStart(object args) {
        Console.WriteLine("Resizing has started.");
    }
}

OnResizeStop

Gets or sets an event callback that is raised when resizing action of the popup is completed in the MultiSelect Dropdown component.

Declaration

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

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<System.Object>	An EventCallback<object> that receives an event argument object containing resize stop data for the popup.

Remarks

Use the OnResizeStop event to perform custom actions after the user finishes resizing the popup. This event is ideal for finalizing layout, saving state, or logging the popup's final size.

Examples

<SfMultiSelect TValue="string[]" AllowResize="true">
    <MultiSelectEvents OnResizeStop="HandleResizeStop" />
</SfMultiSelect>
@code {
    private void HandleResizeStop(object args) {
        Console.WriteLine("Resizing has stopped.");
    }
}

OnValueRemove

Gets or sets an event callback invoked before a value is removed from selection in the MultiSelect Dropdown component.

Declaration

public EventCallback<RemoveEventArgs<TItem>> OnValueRemove { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<RemoveEventArgs<TItem>>	An EventCallback<RemoveEventArgs<TItem>> triggered before a value is removed, allowing custom behavior or cancellation.

Remarks

Use this event to conditionally filter which values can be removed from selection.

OnValueSelect

Gets or sets an event callback invoked when a user selects an item from the dropdown popup in the MultiSelect Dropdown component.

Declaration

public EventCallback<SelectEventArgs<TItem>> OnValueSelect { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<SelectEventArgs<TItem>>	An EventCallback<SelectEventArgs<TItem>> called when selection occurs, providing SelectEventArgs<TItem> to determine or cancel the action.

Remarks

You can prevent the item selection action using SelectEventArgs<TItem>.Cancel.

Examples

<SfMultiSelect TItem="string" TValue="string" DataSource="@MyList">
    <MultiSelectEvents TValue="string" TItem="string" OnValueSelect="@OnSelectHandler"/>
</SfMultiSelect>
@code {
    private List<string> MyList = new List<string>();
    public void OnSelectHandler(SelectEventArgs<string> args) {
        if (args.ItemData == "Medium")
            args.Cancel = true;
    }
}

Opened

Gets or sets an event callback invoked when the dropdown popup is opened for the MultiSelect Dropdown component.

Declaration

public EventCallback<PopupEventArgs> Opened { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<PopupEventArgs>	An EventCallback<PopupEventArgs> called when the popup opens, receiving PopupEventArgs for event data.

Remarks

Use for logging, state control, or to trigger UI effects during popup open.

SelectedAll

Gets or sets an event callback invoked after executing the select all operation in the MultiSelect Dropdown component.

Declaration

public EventCallback<SelectAllEventArgs<TItem>> SelectedAll { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<SelectAllEventArgs<TItem>>	An EventCallback<SelectAllEventArgs<TItem>> triggered after all items are selected.

Remarks

Use this event to respond to select all operations for MultiSelect lists.

SelectingAll

Gets or sets the event callback that will be invoked before the select all process is start in the MultiSelect Dropdown component.

Declaration

public EventCallback<SelectingAllEventArgs<TItem>> SelectingAll { get; set; }

Property Value

Type
Microsoft.AspNetCore.Components.EventCallback<SelectingAllEventArgs<TItem>>

Remarks

To cancel the Select All action, set Cancel. You can prevent the OnValueSelect, OnValueRemove, and ValueRemoved events using SuppressItemEvents.

Examples

<SfMultiSelect TValue="string" TItem="string" DataSource="@MyList" Mode="CheckBox" SelectingAll="OnSelectingAll">
</SfMultiSelect>

@code {
    protected List<string> MyList = new List<string>() { "Small", "Medium", "Large" };

    public void OnSelectingAll(SelectingAllEventArgs<string> args) {
        // You can write the logic here
    }
}

ValueChange

Gets or sets an event callback that is invoked when the Value property changes, either by selection or user model update.

Declaration

public EventCallback<MultiSelectChangeEventArgs<TValue>> ValueChange { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<MultiSelectChangeEventArgs<TValue>>	An EventCallback<MultiSelectChangeEventArgs<TValue>> that is triggered when the value is updated. The event receives MultiSelectChangeEventArgs<TValue>.

Remarks

This event triggers when an item is selected in the popup or when the model value is changed by the user.

Examples

<SfMultiSelect TItem="string" TValue="string" DataSource="@MyList">
    <MultiSelectEvents TValue="string" TItem="string" ValueChange="@OnChange"/>
</SfMultiSelect>
@code {
    private List<string> MyList = new List<string>();
    public void OnChange(MultiSelectChangeEventArgs<string> args) {
        // New value is args.Value
    }
}

ValueRemoved

Gets or sets an event callback invoked after a value has been removed from selection in the MultiSelect Dropdown component.

Declaration

public EventCallback<RemoveEventArgs<TItem>> ValueRemoved { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<RemoveEventArgs<TItem>>	An EventCallback<RemoveEventArgs<TItem>> called after a value has been removed, receiving RemoveEventArgs<TItem>.

Remarks

Use this event to respond to value removals, such as updates to external lists or counters.

Methods

ComponentDispose(Boolean)

Declaration

protected void ComponentDispose(bool disposing)

Parameters

Type	Name	Description
System.Boolean	disposing