ListEditItemsRequestedByFilterConditionEventArgs.Filter Property

Gets a string that represents a filter condition for the editor’s items.

Namespace: DevExpress.Web

Assembly: DevExpress.Web.v23.2.dll

NuGet Package: DevExpress.Web

Declaration

C#

public string Filter { get; }

VB.NET

Public ReadOnly Property Filter As String

Property Value

Type	Description
String	A string value that represents a filter condition.

Example

The following section of the Filtering Large Data Source online demo illustrates how the ASPxComboBox.ItemsRequestedByFilterCondition and ASPxComboBox.ItemRequestedByValue events of the ASPxComboBox editor can be handled to filter the editor’s data source containing a large number of records.

Note

To work properly, both the ItemsRequestedByFilterCondition and ItemRequestedByValue events should be handled.

C#

protected void ASPxComboBox_OnItemsRequestedByFilterCondition_SQL(object source, 
ListEditItemsRequestedByFilterConditionEventArgs e) {
         ASPxComboBox comboBox = (ASPxComboBox)source;
         SqlDataSource1.SelectCommand = @"SELECT OID, [From], Sent, Subject 
             FROM (select OID, [From], Sent, Subject, row_number() over(order by t.Sent) as [rn] 
             from dbo.ServerSideGridTest as t WHERE ((t.Subject LIKE @filter) OR (t.[From] 
              LIKE @filter))) as st where st.[rn] between @startIndex and @endIndex";
         SqlDataSource1.SelectParameters.Clear();
         SqlDataSource1.SelectParameters.Add("filter", TypeCode.String, string.Format("%{0}%", e.Filter));
         SqlDataSource1.SelectParameters.Add("startIndex", TypeCode.Int64, (e.BeginIndex + 1).ToString());
         SqlDataSource1.SelectParameters.Add("endIndex", TypeCode.Int64, (e.EndIndex + 1).ToString());
         comboBox.DataSource = SqlDataSource1;
         comboBox.DataBind();
}

protected void ASPxComboBox_OnItemRequestedByValue_SQL(object source, 
ListEditItemRequestedByValueEventArgs e) {
    ASPxComboBox comboBox = (ASPxComboBox)source;
    SqlDataSource1.SelectCommand = @"SELECT OID, Subject, [From], Sent 
        FROM dbo.ServerSideGridTest WHERE (OID = @OID) ORDER BY Sent";
    SqlDataSource1.SelectParameters.Add("OID", TypeCode.Int64, e.Value.ToString());
    ...
    comboBox.DataSource = SqlDataSource1;
    comboBox.DataBind();
}

ASPX

<dxe:ASPxComboBox ID="ASPxComboBox1" runat="server" 
EnableCallbackMode="true" CallbackPageSize="10" 
    IncrementalFilteringMode="Contains" ValueType="System.String" ValueField="OID" 
    OnItemsRequestedByFilterCondition="ASPxComboBox_OnItemsRequestedByFilterCondition_SQL" 
    OnItemRequestedByValue="ASPxComboBox_OnItemRequestedByValue_SQL"  
    TextFormatString="{0};{1}" TextField="From" Width="100%" DropDownWidth="610">
    <Columns>
        <dxe:ListBoxColumn FieldName="Subject" Width="300px"/>
        <dxe:ListBoxColumn FieldName="From" Width="80px"/>
        <dxe:ListBoxColumn FieldName="Sent"/>
    </Columns>
</dxe:ASPxComboBox>