RadzenDropDown<TValue> Class

RadzenDropDown<TValue>link

A dropdown select component that allows users to choose one or multiple items from a popup list. RadzenDropDown supports data binding, filtering, templates, virtual scrolling, and both single and multiple selection modes. Binds to a data source via the Data property and uses TextProperty and ValueProperty to determine what to display and what value to bind. Supports filtering (with configurable operators and case sensitivity), custom item templates, empty state templates, value templates for the selected item display, and can be configured as editable to allow custom text entry. For multiple selection, set Multiple=true and bind to a collection type.

Declaration

public RadzenDropDown<TValue>()

Chipslink

Gets or sets whether selected items should be displayed as removable chips in the input area. When enabled in multiple selection mode, each selected item appears as a chip with an X button for quick removal. Requires Multiple to be set to true.

Declaration

public bool Chips { get; set; }

Property Value

ClearSearchAfterSelectionlink

Gets or sets whether the filter search text should be cleared after an item is selected. When true, selecting an item will reset the filter, showing all items again on the next open.

Declaration

public bool ClearSearchAfterSelection { get; set; }

Property Value

Closelink

Callback for when a dropdown is closed.

Declaration

public EventCallback Close { get; set; }

Property Value

EmptyTemplatelink

Gets or sets the template displayed when the dropdown data source is empty or no items match the filter. Use this to show a custom "No items found" or "Empty list" message.

Declaration

public RenderFragment EmptyTemplate { get; set; }

Property Value

FilterAutoCompleteTypelink

Gets or sets the HTML autocomplete attribute value for the filter search input. Controls whether the browser should provide autocomplete suggestions for the filter field.

Declaration

public AutoCompleteType FilterAutoCompleteType { get; set; }

Property Value

FilterPlaceholderlink

Gets or sets the placeholder text displayed in the filter search box within the dropdown popup. This helps users understand they can filter the list by typing.

Declaration

public string FilterPlaceholder { get; set; }

Property Value

FooterTemplatelink

Gets or sets the footer template.

Declaration

public RenderFragment FooterTemplate { get; set; }

Property Value

InputAttributeslink

Gets or sets additional HTML attributes to be applied to the underlying input element. This allows passing custom attributes like data-* attributes, aria-* attributes, or other HTML attributes directly to the input.

Declaration

public IReadOnlyDictionary<string, object> InputAttributes { get; set; }

Property Value

ItemRenderlink

Gets or sets a callback invoked when rendering each dropdown item. Use this to customize item attributes, such as adding CSS classes or data attributes based on item properties.

Declaration

public Action<DropDownItemRenderEventArgs<TValue>> ItemRender { get; set; }

Property Value

MaxSelectedLabelslink

Gets or sets the maximum number of selected item labels to display in the input before showing a count summary. When multiple selection is enabled and more items are selected than this value, the input will show "N items selected" instead of listing all labels. Only applicable when Multiple is true.

Declaration

public int MaxSelectedLabels { get; set; }

Property Value

Openlink

Callback for when a dropdown is opened.

Declaration

public EventCallback Open { get; set; }

Property Value

OpenOnFocuslink

Gets or sets whether the dropdown popup should automatically open when the input receives focus. Useful for improving user experience by reducing clicks needed to interact with the dropdown.

Declaration

public bool OpenOnFocus { get; set; }

Property Value

OpenPopupKeylink

Gets or sets the keyboard key that triggers opening the popup when OpenOnFocus is enabled. Default is "Enter".

Declaration

public string OpenPopupKey { get; set; }

Property Value

PopupStylelink

Gets or sets the CSS style applied to the dropdown popup container. Use this to control the popup dimensions, especially max-height to limit scrollable area.

Declaration

public string PopupStyle { get; set; }

Property Value

ReadOnlylink

Gets or sets whether the dropdown is read-only and cannot be changed by user interaction. When true, the dropdown displays the selected value but prevents changing the selection.

Declaration

public bool ReadOnly { get; set; }

Property Value

SelectAllTextlink

Gets or sets the select all text.

Declaration

public string SelectAllText { get; set; }

Property Value

SelectedItemsTextlink

Gets or sets the selected items text.

Declaration

public string SelectedItemsText { get; set; }

Property Value

ValueTemplatelink

Gets or sets the template used to render the currently selected value in the dropdown input. This allows custom formatting or layout for the displayed selection. The template receives the selected item as context.

Declaration

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

Property Value

BuildRenderTreelink

Declaration

protected override void BuildRenderTree(Rendering.RenderTreeBuilder __builder)

Parameters

Disposelink

Declaration

public override void Dispose()

GetComponentCssClasslink

Declaration

protected override string GetComponentCssClass()

Returns

HandleKeyPresslink

Declaration

protected override Task HandleKeyPress(KeyboardEventArgs args, bool isFilter, bool? shouldSelectOnChange)

Parameters

Returns

OnAfterRenderAsynclink

Declaration

protected override Task OnAfterRenderAsync(bool firstRender)

Parameters

Returns

OnCloselink

Called when popup is closed.

Declaration

public Task OnClose()

Returns

OnSelectItemlink

Called when item is selected.

Declaration

protected override Task OnSelectItem(object item, bool isFromKey)

Parameters

Returns

OpenPopuplink

Opens the popup.

Declaration

protected override Task OpenPopup(string key, bool isFilter, bool isFromClick)

Parameters

Returns

SelectAlllink

Declaration

protected override Task SelectAll()

Returns

SetParametersAsynclink

Declaration

public override Task SetParametersAsync(ParameterView parameters)

Parameters

Returns