ASPxGridView.DataColumns Property
Gets the collection of all data columns within the ASPxGridView control.
Namespace: DevExpress.Web
Assembly:
DevExpress.Web.v20.2.dll
NuGet Package:
DevExpress.Web
Declaration
public ReadOnlyGridColumnCollection<GridViewDataColumn> DataColumns { get; }
Public ReadOnly Property DataColumns As ReadOnlyGridColumnCollection(Of GridViewDataColumn)
Property Value
The DataColumns property provides access to a collection that contains data columns of the ASPxGridView control. This collection is read-only, since individual columns can be manipulated (added or removed) at the level of a grid control (ASPxGridView.Columns). The collection obtained via the DataColumns property allows you to easily iterate through data grid columns and access any required column identified by its name, field name, or caption.
Example
In some cases, when the default filter row editor’s functionality is not enough, you can provide custom filter cell content using the GridViewColumn.FilterTemplate.
In this example, a default cell editor is replaced with the ASPxGridLookup control. The control’s ASPxClientEdit.ValueChanged client-side event is used to send a callback to the server side, invoking the grid’s ASPxGridView.CustomCallback event. In the event handler, a filter criteria is created and applied to the grid using the ASPxGridView.ApplyFilterToColumn method.
View Example
using DevExpress.Data.Filtering;
using DevExpress.Web.ASPxGridLookup;
using DevExpress.Web.ASPxGridView;
public partial class _Default : System.Web.UI.Page {
protected void Grid_CustomCallback(object sender, ASPxGridViewCustomCallbackEventArgs e) {
if(e.Parameters == "FilterByCategories") {
var column = Grid.DataColumns["CategoryName"];
var lookup = Grid.FindFilterCellTemplateControl(column, "Lookup") as ASPxGridLookup;
if(lookup != null)
Grid.ApplyFilterToColumn(column, CreateCriteria(lookup, column.FieldName));
}
}
protected CriteriaOperator CreateCriteria(ASPxGridLookup gridLookup, string fieldName) {
var values = gridLookup.GridView.GetSelectedFieldValues(fieldName);
return values.Count > 0 ? new InOperator(fieldName, values) : null;
}
}
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>
<%@ Register Assembly="DevExpress.Web.v13.1" Namespace="DevExpress.Web.ASPxGridView" TagPrefix="dx" %>
<%@ Register Assembly="DevExpress.Web.v13.1" Namespace="DevExpress.Web.ASPxEditors" TagPrefix="dx" %>
<%@ Register Assembly="DevExpress.Web.v13.1" Namespace="DevExpress.Web.ASPxGridLookup" TagPrefix="dx" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
<script type="text/javascript">
function Lookup_ValueChanged(s, e) {
grid.PerformCallback("FilterByCategories");
}
</script>
</head>
<body>
<form id="form1" runat="server">
<dx:ASPxGridView runat="server" ID="Grid" AutoGenerateColumns="False" DataSourceID="ProductsDataSource" ClientInstanceName="grid"
OnCustomCallback="Grid_CustomCallback" EnableViewState="false">
<Columns>
<dx:GridViewDataTextColumn FieldName="CategoryName">
<FilterTemplate>
<dx:ASPxGridLookup runat="server" ID="Lookup" AutoGenerateColumns="False" DataSourceID="CategoriesDataSource" KeyFieldName="CategoryID"
SelectionMode="Multiple" TextFormatString="{0}" >
<Columns>
<dx:GridViewCommandColumn ShowSelectCheckbox="true" />
<dx:GridViewDataTextColumn FieldName="CategoryName" />
<dx:GridViewDataBinaryImageColumn FieldName="Picture">
<PropertiesBinaryImage ImageWidth="48" />
</dx:GridViewDataBinaryImageColumn>
</Columns>
<ClientSideEvents ValueChanged="Lookup_ValueChanged" />
</dx:ASPxGridLookup>
</FilterTemplate>
</dx:GridViewDataTextColumn>
<dx:GridViewDataTextColumn FieldName="ProductName" />
<dx:GridViewDataTextColumn FieldName="ProductSales" />
<dx:GridViewDataDateColumn FieldName="ShippedDate" />
</Columns>
<Settings ShowFilterRow="true" />
</dx:ASPxGridView>
<asp:AccessDataSource ID="ProductsDataSource" runat="server" DataFile="~/App_Data/nwind.mdb"
SelectCommand="SELECT * FROM [ProductReports]" />
<asp:AccessDataSource ID="CategoriesDataSource" runat="server" DataFile="~/App_Data/nwind.mdb"
SelectCommand="SELECT * FROM [Categories]" />
</form>
</body>
</html>
<%@ Page Language="vb" AutoEventWireup="true" CodeFile="Default.aspx.vb" Inherits="_Default" %>
<%@ Register Assembly="DevExpress.Web.v13.1" Namespace="DevExpress.Web.ASPxGridView" TagPrefix="dx" %>
<%@ Register Assembly="DevExpress.Web.v13.1" Namespace="DevExpress.Web.ASPxEditors" TagPrefix="dx" %>
<%@ Register Assembly="DevExpress.Web.v13.1" Namespace="DevExpress.Web.ASPxGridLookup" TagPrefix="dx" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
<script type="text/javascript">
function Lookup_ValueChanged(s, e) {
grid.PerformCallback("FilterByCategories");
}
</script>
</head>
<body>
<form id="form1" runat="server">
<dx:ASPxGridView runat="server" ID="Grid" AutoGenerateColumns="False" DataSourceID="ProductsDataSource" ClientInstanceName="grid"
OnCustomCallback="Grid_CustomCallback" EnableViewState="false">
<Columns>
<dx:GridViewDataTextColumn FieldName="CategoryName">
<FilterTemplate>
<dx:ASPxGridLookup runat="server" ID="Lookup" AutoGenerateColumns="False" DataSourceID="CategoriesDataSource" KeyFieldName="CategoryID"
SelectionMode="Multiple" TextFormatString="{0}" >
<Columns>
<dx:GridViewCommandColumn ShowSelectCheckbox="true" />
<dx:GridViewDataTextColumn FieldName="CategoryName" />
<dx:GridViewDataBinaryImageColumn FieldName="Picture">
<PropertiesBinaryImage ImageWidth="48" />
</dx:GridViewDataBinaryImageColumn>
</Columns>
<ClientSideEvents ValueChanged="Lookup_ValueChanged" />
</dx:ASPxGridLookup>
</FilterTemplate>
</dx:GridViewDataTextColumn>
<dx:GridViewDataTextColumn FieldName="ProductName" />
<dx:GridViewDataTextColumn FieldName="ProductSales" />
<dx:GridViewDataDateColumn FieldName="ShippedDate" />
</Columns>
<Settings ShowFilterRow="true" />
</dx:ASPxGridView>
<asp:AccessDataSource ID="ProductsDataSource" runat="server" DataFile="~/App_Data/nwind.mdb"
SelectCommand="SELECT * FROM [ProductReports]" />
<asp:AccessDataSource ID="CategoriesDataSource" runat="server" DataFile="~/App_Data/nwind.mdb"
SelectCommand="SELECT * FROM [Categories]" />
</form>
</body>
</html>
Imports DevExpress.Data.Filtering
Imports DevExpress.Web.ASPxGridLookup
Imports DevExpress.Web.ASPxGridView
Partial Public Class _Default
Inherits System.Web.UI.Page
Protected Sub Grid_CustomCallback(ByVal sender As Object, ByVal e As ASPxGridViewCustomCallbackEventArgs)
If e.Parameters = "FilterByCategories" Then
Dim column = Grid.DataColumns("CategoryName")
Dim lookup = TryCast(Grid.FindFilterCellTemplateControl(column, "Lookup"), ASPxGridLookup)
If lookup IsNot Nothing Then
Grid.ApplyFilterToColumn(column, CreateCriteria(lookup, column.FieldName))
End If
End If
End Sub
Protected Function CreateCriteria(ByVal gridLookup As ASPxGridLookup, ByVal fieldName As String) As CriteriaOperator
Dim values = gridLookup.GridView.GetSelectedFieldValues(fieldName)
Return If(values.Count > 0, New InOperator(fieldName, values), Nothing)
End Function
End Class
See Also