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MultiSelect Filter

The MultiSelect component can filter the available suggestions according to the current user input, so they can find the one they need faster. To see the difference in behavior, visit the Live Demo: MultiSelect Filtering page.

To enable filtering, set the Filterable parameter to true. The filtering is case insensitive. You can also implement custom (server) filtering and set a data source dynamically through the OnRead event.

Filtering looks in the TextField, and the filter is reset when the dropdown closes.

Filter Operator

The default filter operator is starts with. You can choose a different operator through the FilterOperator parameter that takes a member of the Telerik.Blazor.StringFilterOperator enum.

Minimum Length

To control when the filter list appears, set the MinLength parameter. This can be useful if you have a very large list of data or a lot of similar items.


By default, the filtering is debounced with 150ms. Configure that with the DebounceDelay parameter of the component.

Filtering Example

Filtering in the MultiSelect

            Filter operator:
            <TelerikDropDownList @bind-Value="@FilterOperator"
                                 Width="160px" />
            Minimum string length before filtering:
            <TelerikNumericTextBox @bind-Value="@FilterMinLength" Min="0" Width="100px" />
            Debounce delay:
            <TelerikNumericTextBox @bind-Value="@DebounceDelay" Min="0" Width="120px" />

<br />

<TelerikMultiSelect Data="@ProductList"
                    Placeholder="Type digits to see filtering in action"

    private List<Product> ProductList { get; set; }

    private List<int> SelectedProducts { get; set; }

    private List<StringFilterOperator> FilterOperators =>

    private StringFilterOperator FilterOperator { get; set; } = StringFilterOperator.StartsWith;

    private int FilterMinLength { get; set; } = 1;

    private int DebounceDelay { get; set; } = 150;

    protected override void OnInitialized()
        ProductList = new List<Product>();

        for (int i = 1; i <= 30; i++)
            ProductList.Add(new Product()
                Id = i,
                Name = $"{i} Product {i * 111}"


    public class Product
        public int Id { get; set; }
        public string Name { get; set; }

See Also

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