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V25.1
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    DropDownBoxQueryDisplayTextContext Class

    Stores information about editor value and text.

    Namespace: DevExpress.Blazor

    Assembly: DevExpress.Blazor.v25.1.dll

    NuGet Package: DevExpress.Blazor

    #Declaration

    C#
    public class DropDownBoxQueryDisplayTextContext

    #Remarks

    The DxDropDownBox‘s input element is read-only for users. When you specify editor Value programmatically, implement the QueryDisplayText function to define how the editor value is displayed in the input element.

    The function encapsulates an object of the DropDownBoxQueryDisplayTextContext type that contains the editor value (Value) and the previous input text (DisplayText).

    Run Demo: DropDown Box - Multiple Selection ListBox

    Razor
    <label for="ddbMultipleSelectionListBox" class="demo-text cw-480 mb-1">Employees</label>
    <DxDropDownBox @bind-Value="Value"
                   QueryDisplayText="QueryText"
                   DropDownWidthMode="DropDownWidthMode.EditorWidth"
                   SizeMode="Params.SizeMode"
                   InputId="ddbMultipleSelectionListBox"
                   CssClass="cw-480">
        <DropDownBodyTemplate>
            <DxListBox Data="@ListBoxData" TData="Employee" TValue="Employee"
                       Values="@(GetListBoxValues(context.DropDownBox))"
                       ValuesChanged="@(values => ListBoxValuesChanged(values, context.DropDownBox))"
                       TextFieldName="@nameof(Employee.Text)"
                       SelectionMode="ListBoxSelectionMode.Multiple"
                       ShowCheckboxes="true"
                       ShowSearchBox="true"
                       CssClass="templateListbox"
                       >
            </DxListBox>
        </DropDownBodyTemplate>
    </DxDropDownBox>
    
    @code {
        IEnumerable<Employee> ListBoxData { get; set; }
        object Value { get; set; }
    
        string QueryText(DropDownBoxQueryDisplayTextContext arg) {
            var names = (arg.Value as IEnumerable<Employee>)?.Select(x => x.LastName);
            return names != null ? string.Join(",", names) : string.Empty;
        }
    
        IEnumerable<Employee> GetListBoxValues(IDropDownBox dropDownBox) {
            return dropDownBox.Value as IEnumerable<Employee>;
        }
    
        void ListBoxValuesChanged(IEnumerable<Employee> values, IDropDownBox dropDownBox) {
            dropDownBox.BeginUpdate();
            dropDownBox.Value = values;
            dropDownBox.EndUpdate();
    }
    
    protected override async Task OnInitializedAsync() {
        ListBoxData = await NwindDataService.GetEmployeesAsync();
        Value = ListBoxData.Take(2);
    }
    

    ListBox in DropDown Box

    #Inheritance

    Object
    DropDownBoxQueryDisplayTextContext
    See Also