Add/Remove Items in Blazor ListBox Component

4 Nov 20254 minutes to read

Use the AddItemsAsync method can be used. In the following example, the Ferrari LaFerrari and McLaren P1 items when clicking the Add Items button. Items should conform to the TItem type and field mappings (Text and Value) configured in ListBoxFieldSettings. AddItemsAsync also supports an optional index parameter to insert items at a specific position; when omitted, items are appended.

@using Syncfusion.Blazor.DropDowns
@using Syncfusion.Blazor.Buttons

<SfListBox TValue="string[]" TItem="VehicleData" DataSource="@Vehicles" @ref="ListBoxObj">
  <ListBoxFieldSettings Text="Text" Value="Id" />
</SfListBox>
<SfButton @onclick="addData">ADD ITEMS</SfButton>

@code {
      SfListBox<string[],VehicleData> ListBoxObj;
      public List<VehicleData> Vehicles = new List<VehicleData> {
        new VehicleData { Text = "Hennessey Venom", Id = "Vehicle-01" },
        new VehicleData { Text = "Bugatti Chiron", Id = "Vehicle-02" },
        new VehicleData { Text = "Bugatti Veyron Super Sport", Id = "Vehicle-03" },
        new VehicleData { Text = "SSC Ultimate Aero", Id = "Vehicle-04" },
        new VehicleData { Text = "Koenigsegg CCR", Id = "Vehicle-05" },
        new VehicleData { Text = "McLaren F1", Id = "Vehicle-06" },
        new VehicleData { Text = "Aston Martin One- 77", Id = "Vehicle-07" },
        new VehicleData { Text = "Jaguar XJ220", Id = "Vehicle-08" }
    };

    public class VehicleData {
      public string Text  { get; set; }
      public string Id  { get; set; }
    }

      public List<VehicleData> Item = new List<VehicleData>{
        new VehicleData{ Text = "Ferrari LaFerrari", Id = "Vehicle-09"},
        new VehicleData{ Text = "McLaren P1", Id = "Vehicle-10"}
      };

      private async Task addData() {
        await ListBoxObj.AddItems(Item);
      }
}

Remove items from the listbox

Use the RemoveItemAsync method can be used. In the following example, the Ferrari LaFerrari and McLaren P1 items will be removed while clicking Remove Items button. Removed items must match the TItem type and the field mappings used by the ListBox. RemoveItemAsync also supports an optional index parameter to target positions when needed.

@using Syncfusion.Blazor.DropDowns
@using Syncfusion.Blazor.Buttons

<SfListBox TValue="string[]" TItem="VehicleData" DataSource="@Vehicles" @ref="ListBoxObj">
  <ListBoxFieldSettings Text="Text" Value="Id" />
</SfListBox>
<SfButton @onclick="removeData">REMOVE ITEMS</SfButton>

@code {
      SfListBox<string[],VehicleData> ListBoxObj;
      public List<VehicleData> Vehicles = new List<VehicleData> {
        new VehicleData { Text = "Hennessey Venom", Id = "Vehicle-01" },
        new VehicleData { Text = "Bugatti Chiron", Id = "Vehicle-02" },
        new VehicleData { Text = "Bugatti Veyron Super Sport", Id = "Vehicle-03" },
        new VehicleData { Text = "SSC Ultimate Aero", Id = "Vehicle-04" },
        new VehicleData { Text = "Koenigsegg CCR", Id = "Vehicle-05" },
        new VehicleData { Text = "McLaren F1", Id = "Vehicle-06" },
        new VehicleData { Text = "Aston Martin One- 77", Id = "Vehicle-07" },
        new VehicleData { Text = "Jaguar XJ220", Id = "Vehicle-08" },
        new VehicleData{ Text = "Ferrari LaFerrari", Id = "Vehicle-09"},
        new VehicleData{ Text = "McLaren P1", Id = "Vehicle-10"}
    };

    public class VehicleData {
      public string Text  { get; set; }
      public string Id  { get; set; }
    }

    public List<VehicleData> Item = new List<VehicleData>{
        new VehicleData{ Text = "Ferrari LaFerrari", Id = "Vehicle-09"},
        new VehicleData{ Text = "McLaren P1", Id = "Vehicle-10"}
    };

    private async Task removeData() {
      await ListBoxObj.RemoveItemAsync(Item);
    }
}