TemplateField.HeaderTemplate Property
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Gets or sets the template for displaying the header section of a TemplateField object.
public:
virtual property System::Web::UI::ITemplate ^ HeaderTemplate { System::Web::UI::ITemplate ^ get(); void set(System::Web::UI::ITemplate ^ value); };[System.ComponentModel.Browsable(false)]
[System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerProperty)]
[System.Web.UI.TemplateContainer(typeof(System.Web.UI.IDataItemContainer))]
public virtual System.Web.UI.ITemplate HeaderTemplate { get; set; }[<System.ComponentModel.Browsable(false)>]
[<System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerProperty)>]
[<System.Web.UI.TemplateContainer(typeof(System.Web.UI.IDataItemContainer))>]
member this.HeaderTemplate : System.Web.UI.ITemplate with get, setPublic Overridable Property HeaderTemplate As ITemplateProperty Value
A ITemplate-implemented object that contains the template for displaying the header section of a TemplateField in a data-bound control. The default is null, which indicates that this property is not set.
- Attributes
Examples
The following code example demonstrates how to use the HeaderTemplate property to create a custom template for the header section of a TemplateField field column in a GridView control. The template displays a check box that allows the user to show or hide the rows of the GridView control.
<%@ Page language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
void SelectAllCheckBox_CheckedChanged(Object sender, EventArgs e)
{
// Get the CheckBox control that indicates whether to show or
// hide the rows in the GridView control. The sender parameter
// contains the control that raised the event.
CheckBox showCheckBox = (CheckBox)sender;
// Show or hide the rows of the GridView control based
// on the check box value selected by the user.
if (showCheckBox.Checked)
{
ShowRows (true);
}
else
{
ShowRows (false);
}
}
void ShowRows(bool show)
{
// Iterate through the Rows collection of the GridView
// control and show or hide the rows based on the value
// of the show parameter.
foreach(GridViewRow row in AuthorsGridView.Rows)
{
row.Visible = show;
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>TemplateField HeaderTemplate Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>TemplateField HeaderTemplate Example</h3>
<!-- Populate the Columns collection declaratively. -->
<!-- Create a TemplateField column field that contains -->
<!-- a CheckBox control in the header section to show or -->
<!-- hide the rows in the GridView control. -->
<asp:gridview id="AuthorsGridView"
datasourceid="AuthorsSqlDataSource"
autogeneratecolumns="False"
width="250"
runat="server">
<columns>
<asp:templatefield>
<headerstyle backcolor="Navy"
forecolor="White"/>
<itemtemplate>
<%#Eval("au_fname")%>
<%#Eval("au_lname")%>
</itemtemplate>
<headertemplate>
<asp:checkbox id="ShowAllCheckBox"
text="Show All"
checked="True"
autopostback="true"
oncheckedchanged="SelectAllCheckBox_CheckedChanged"
runat="server"/>
</headertemplate>
</asp:templatefield>
</columns>
</asp:gridview>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Pubs sample database. -->
<asp:sqldatasource id="AuthorsSqlDataSource"
selectcommand="SELECT [au_id], [au_lname], [au_fname], [address], [city], [state], [zip], [contract] FROM [authors]"
connectionstring="server=localhost;database=pubs;integrated security=SSPI"
runat="server">
</asp:sqldatasource>
</form>
</body>
</html>
<%@ Page language="VB" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
Sub SelectAllCheckBox_CheckedChanged(ByVal sender As Object, ByVal e As EventArgs)
' Get the CheckBox control that indicates whether to show or
' hide the rows in the GridView control. The sender parameter
' contains the control that raised the event.
Dim showCheckBox As CheckBox = CType(sender, CheckBox)
' Show or hide the rows of the GridView control based
' on the check box value selected by the user.
If showCheckBox.Checked Then
ShowRows(True)
Else
ShowRows(False)
End If
End Sub
Sub ShowRows(ByVal show As Boolean)
' Iterate through the Rows collection of the GridView
' control and show or hide the rows based on the value
' of the show parameter.
Dim row As GridViewRow
For Each row In AuthorsGridView.Rows
row.Visible = show
Next
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>TemplateField HeaderTemplate Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>TemplateField HeaderTemplate Example</h3>
<!-- Populate the Columns collection declaratively. -->
<!-- Create a TemplateField column field that contains -->
<!-- a CheckBox control in the header section to show or -->
<!-- hide the rows in the GridView control. -->
<asp:gridview id="AuthorsGridView"
datasourceid="AuthorsSqlDataSource"
autogeneratecolumns="False"
width="250"
runat="server">
<columns>
<asp:templatefield>
<headerstyle backcolor="Navy"
forecolor="White"/>
<itemtemplate>
<%#Eval("au_fname")%>
<%#Eval("au_lname")%>
</itemtemplate>
<headertemplate>
<asp:checkbox id="ShowAllCheckBox"
text="Show All"
checked="True"
autopostback="true"
oncheckedchanged="SelectAllCheckBox_CheckedChanged"
runat="server"/>
</headertemplate>
</asp:templatefield>
</columns>
</asp:gridview>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Pubs sample database. -->
<asp:sqldatasource id="AuthorsSqlDataSource"
selectcommand="SELECT [au_id], [au_lname], [au_fname], [address], [city], [state], [zip], [contract] FROM [authors]"
connectionstring="server=localhost;database=pubs;integrated security=SSPI"
runat="server">
</asp:sqldatasource>
</form>
</body>
</html>
Remarks
Use the HeaderTemplate property to specify the custom content displayed for the header section of a TemplateField object. Define the content by creating a template that specifies how the header section is rendered.
To specify a template, first place opening and closing <HeaderTemplate> tags between the opening and closing tags of the <TemplateField> element. Next, add the custom content between the opening and closing <HeaderTemplate> tags. The content can be as simple as plain text or more complex (embedding other controls in the template, for example).
To programmatically access a control defined in a template, first determine which TableCell object in the data-bound control contains the control. Next, use the Controls collection of the TableCell object to access the control. You can also use the FindControl method of the TableCell object to find the control, if the control has an ID property specified.
