DataGrid.HeaderStyle 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 the style properties of the heading section in the DataGrid control.
public:
virtual property System::Web::UI::WebControls::TableItemStyle ^ HeaderStyle { System::Web::UI::WebControls::TableItemStyle ^ get(); };
[System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerProperty)]
public virtual System.Web.UI.WebControls.TableItemStyle HeaderStyle { get; }
[<System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerProperty)>]
member this.HeaderStyle : System.Web.UI.WebControls.TableItemStyle
Public Overridable ReadOnly Property HeaderStyle As TableItemStyle
Property Value
A TableItemStyle object that contains the style properties of the heading section in the DataGrid control. The default value is an empty TableItemStyle object.
- Attributes
Examples
The following code example demonstrates how to use the HeaderStyle property to set the background color of the heading section.
<%@ Page Language="C#" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<!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" >
<script language="C#" runat="server">
ICollection CreateDataSource()
{
DataTable dt = new DataTable();
DataRow dr;
dt.Columns.Add(new DataColumn("IntegerValue", typeof(Int32)));
dt.Columns.Add(new DataColumn("StringValue", typeof(string)));
dt.Columns.Add(new DataColumn("DateTimeValue", typeof(string)));
dt.Columns.Add(new DataColumn("BoolValue", typeof(bool)));
for (int i = 0; i < 100; i++) {
dr = dt.NewRow();
dr[0] = i;
dr[1] = "Item " + i.ToString();
dr[2] = DateTime.Now.ToShortDateString();
dr[3] = (i % 2 != 0) ? true : false;
dt.Rows.Add(dr);
}
DataView dv = new DataView(dt);
return dv;
}
void Page_Load(Object sender, EventArgs e)
{
if (chk1.Checked)
MyDataGrid.PagerStyle.Mode = PagerMode.NumericPages;
else
MyDataGrid.PagerStyle.Mode = PagerMode.NextPrev;
BindGrid();
}
void MyDataGrid_Page(Object sender, DataGridPageChangedEventArgs e)
{
MyDataGrid.CurrentPageIndex = e.NewPageIndex;
BindGrid();
}
void BindGrid()
{
MyDataGrid.DataSource = CreateDataSource();
MyDataGrid.DataBind();
ShowStats();
}
void ShowStats()
{
lblEnabled.Text = "AllowPaging is " + MyDataGrid.AllowPaging;
lblCurrentIndex.Text = "CurrentPageIndex is " + MyDataGrid.CurrentPageIndex;
lblPageCount.Text = "PageCount is " + MyDataGrid.PageCount;
lblPageSize.Text = "PageSize is " + MyDataGrid.PageSize;
}
</script>
<head runat="server">
<title>DataGrid Example</title>
</head>
<body>
<h3>DataGrid Example</h3>
<form id="form1" runat="server">
<asp:DataGrid id="MyDataGrid" runat="server"
AllowPaging="True"
PageSize="10"
ShowFooter="true"
OnPageIndexChanged="MyDataGrid_Page"
BorderColor="black"
BorderWidth="1"
GridLines="Both"
CellPadding="3"
CellSpacing="0"
Font-Names="Verdana"
Font-Size="8pt">
<PagerStyle Mode="NumericPages"
HorizontalAlign="Right">
</PagerStyle>
<HeaderStyle BackColor="#aaaadd">
</HeaderStyle>
<FooterStyle BackColor="#aaaadd">
</FooterStyle>
<AlternatingItemStyle BackColor="#eeeeee">
</AlternatingItemStyle>
</asp:DataGrid>
<br />
<asp:Checkbox id="chk1" runat="server"
Text="Show numeric page navigation buttons"
Font-Names="Verdana"
Font-Size="8pt"
AutoPostBack="true"/>
<br />
<table style="background-color:#eeeeee; padding:6">
<tr>
<td style="display:inline">
<asp:Label id="lblEnabled"
runat="server"/><br />
<asp:Label id="lblCurrentIndex"
runat="server"/><br />
<asp:Label id="lblPageCount"
runat="server"/><br />
<asp:Label id="lblPageSize"
runat="server"/><br />
</td>
</tr>
</table>
</form>
</body>
</html>
<%@ Page Language="VB" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<!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" >
<script language="VB" runat="server">
Function CreateDataSource() As ICollection
Dim dt As New DataTable()
Dim dr As DataRow
dt.Columns.Add(New DataColumn("IntegerValue", GetType(Int32)))
dt.Columns.Add(New DataColumn("StringValue", GetType(String)))
dt.Columns.Add(New DataColumn("DateTimeValue", GetType(String)))
dt.Columns.Add(New DataColumn("BoolValue", GetType(Boolean)))
Dim i As Integer
For i = 0 To 99
dr = dt.NewRow()
dr(0) = i
dr(1) = "Item " + i.ToString()
dr(2) = DateTime.Now.ToShortDateString()
If i Mod 2 <> 0 Then
dr(3) = True
Else
dr(3) = False
End If
dt.Rows.Add(dr)
Next i
Dim dv As New DataView(dt)
Return dv
End Function 'CreateDataSource
Sub Page_Load(sender As Object, e As EventArgs)
If chk1.Checked Then
MyDataGrid.PagerStyle.Mode = PagerMode.NumericPages
Else
MyDataGrid.PagerStyle.Mode = PagerMode.NextPrev
End If
BindGrid()
End Sub 'Page_Load
Sub MyDataGrid_Page(sender As Object, e As DataGridPageChangedEventArgs)
MyDataGrid.CurrentPageIndex = e.NewPageIndex
BindGrid()
End Sub 'MyDataGrid_Page
Sub BindGrid()
MyDataGrid.DataSource = CreateDataSource()
MyDataGrid.DataBind()
ShowStats()
End Sub 'BindGrid
Sub ShowStats()
lblEnabled.Text = "AllowPaging is " & MyDataGrid.AllowPaging
lblCurrentIndex.Text = "CurrentPageIndex is " & MyDataGrid.CurrentPageIndex
lblPageCount.Text = "PageCount is " & MyDataGrid.PageCount
lblPageSize.Text = "PageSize is " & MyDataGrid.PageSize
End Sub 'ShowStats
</script>
<head runat="server">
<title>DataGrid Example</title>
</head>
<body>
<h3>DataGrid Example</h3>
<form id="form1" runat="server">
<asp:DataGrid id="MyDataGrid" runat="server"
AllowPaging="True"
PageSize="10"
ShowFooter="true"
OnPageIndexChanged="MyDataGrid_Page"
BorderColor="black"
BorderWidth="1"
GridLines="Both"
CellPadding="3"
CellSpacing="0"
Font-Names="Verdana"
Font-Size="8pt">
<PagerStyle Mode="NumericPages"
HorizontalAlign="Right">
</PagerStyle>
<HeaderStyle BackColor="#aaaadd">
</HeaderStyle>
<FooterStyle BackColor="#aaaadd">
</FooterStyle>
<AlternatingItemStyle BackColor="#eeeeee">
</AlternatingItemStyle>
</asp:DataGrid>
<br />
<asp:Checkbox id="chk1" runat="server"
Text="Show numeric page navigation buttons"
Font-Names="Verdana"
Font-Size="8pt"
AutoPostBack="true"/>
<br />
<table style="background-color:#eeeeee; padding:6">
<tr>
<td style="display:inline">
<asp:Label id="lblEnabled"
runat="server"/><br />
<asp:Label id="lblCurrentIndex"
runat="server"/><br />
<asp:Label id="lblPageCount"
runat="server"/><br />
<asp:Label id="lblPageSize"
runat="server"/><br />
</td>
</tr>
</table>
</form>
</body>
</html>
<%@ Page Language="C#" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<!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" >
<script runat="server">
ICollection CreateDataSource()
{
// Create sample data for the DataGrid control.
DataTable dt = new DataTable();
DataRow dr;
// Define the columns of the table.
dt.Columns.Add(new DataColumn("IntegerValue", typeof(Int32)));
dt.Columns.Add(new DataColumn("StringValue", typeof(string)));
dt.Columns.Add(new DataColumn("CurrencyValue", typeof(double)));
// Populate the table with sample values.
for (int i = 0; i < 5; i++)
{
dr = dt.NewRow();
dr[0] = i;
dr[1] = "Item " + i.ToString();
dr[2] = 1.23 * (i + 1);
dt.Rows.Add(dr);
}
DataView dv = new DataView(dt);
return dv;
}
void Page_Load(Object sender, EventArgs e)
{
// Load sample data only once when the page is first loaded.
if (!IsPostBack)
{
ItemsGrid.DataSource = CreateDataSource();
ItemsGrid.DataBind();
}
}
void Button_Click(Object sender, EventArgs e)
{
// Count the number of selected items in the DataGrid control.
int count = 0;
// Display the selected times.
Message.Text = "You Selected: <br />";
// Iterate through each item (row) in the DataGrid control and determine
// whether it is selected.
foreach (DataGridItem item in ItemsGrid.Items)
{
DetermineSelection(item, ref count);
}
// If no items are selected, display the appropriate message.
if (count == 0)
{
Message.Text = "Not items selected";
}
}
void DetermineSelection(DataGridItem item, ref int count)
{
// Retrieve the SelectCheckBox CheckBox control from the specified item (row) in the
// DataGrid control.
CheckBox selection = (CheckBox)item.FindControl("SelectCheckBox");
// If the item is selected, display the appropriate message and increment the count
// of selected items.
if (selection != null)
{
if (selection.Checked)
{
Message.Text += "- " + item.Cells[1].Text + "<br />";
count++;
}
}
}
void Selection_Change(Object sender, EventArgs e)
{
// Set the background color for the heading and footer sections of
// the DataGrid control.
ItemsGrid.HeaderStyle.BackColor = System.Drawing.Color.FromName(List.SelectedItem.Value);
ItemsGrid.FooterStyle.BackColor = System.Drawing.Color.FromName(List.SelectedItem.Value);
}
</script>
<head runat="server">
<title>DataGrid HeaderStyle and FooterStyle Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DataGrid HeaderStyle and FooterStyle Example</h3>
Select a backcolor for the header and footer sections.
<br /><br />
<b>Product List</b>
<asp:DataGrid id="ItemsGrid"
BorderColor="black"
BorderWidth="1"
CellPadding="3"
ShowFooter="True"
AutoGenerateColumns="False"
runat="server">
<HeaderStyle BackColor="White">
</HeaderStyle>
<FooterStyle BackColor="White">
</FooterStyle>
<Columns>
<asp:BoundColumn DataField="IntegerValue"
HeaderText="Item"/>
<asp:BoundColumn DataField="StringValue"
HeaderText="Description"/>
<asp:BoundColumn DataField="CurrencyValue"
HeaderText="Price"
DataFormatString="{0:c}">
<ItemStyle HorizontalAlign="Right">
</ItemStyle>
</asp:BoundColumn>
<asp:TemplateColumn HeaderText="Select Item">
<ItemTemplate>
<asp:CheckBox id="SelectCheckBox"
Text="Add to Cart"
Checked="False"
runat="server"/>
</ItemTemplate>
</asp:TemplateColumn>
</Columns>
</asp:DataGrid>
<br /><br />
<asp:Button id="SubmitButton"
Text="Submit"
OnClick = "Button_Click"
runat="server"/>
<br /><br />
<asp:Label id="Message"
runat="server"/>
<hr />
Header and footer backcolor: <br />
<asp:DropDownList id="List"
AutoPostBack="True"
OnSelectedIndexChanged="Selection_Change"
runat="server">
<asp:ListItem Selected="True" Value="White"> White </asp:ListItem>
<asp:ListItem Value="Silver"> Silver </asp:ListItem>
<asp:ListItem Value="DarkGray"> Dark Gray </asp:ListItem>
<asp:ListItem Value="Khaki"> Khaki </asp:ListItem>
<asp:ListItem Value="DarkKhaki"> Dark Khaki </asp:ListItem>
</asp:DropDownList>
</form>
</body>
</html>
<%@ Page Language="VB" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<!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" >
<script runat="server">
Function CreateDataSource() As ICollection
' Create sample data for the DataGrid control.
Dim dt As DataTable = New DataTable()
Dim dr As DataRow
' Define the columns of the table.
dt.Columns.Add(New DataColumn("IntegerValue", GetType(Int32)))
dt.Columns.Add(New DataColumn("StringValue", GetType(string)))
dt.Columns.Add(New DataColumn("CurrencyValue", GetType(double)))
' Populate the table with sample values.
Dim i As Integer
For i = 0 to 4
dr = dt.NewRow()
dr(0) = i
dr(1) = "Item " & i.ToString()
dr(2) = 1.23 * (i + 1)
dt.Rows.Add(dr)
Next i
Dim dv As DataView = New DataView(dt)
Return dv
End Function
Sub Page_Load(sender As Object, e As EventArgs)
' Load sample data only once when the page is first loaded.
If Not IsPostBack Then
ItemsGrid.DataSource = CreateDataSource()
ItemsGrid.DataBind()
End If
End Sub
Sub Button_Click(sender As Object, e As EventArgs)
' Count the number of selected items in the DataGrid control.
Dim count As Integer = 0
' Display the selected times.
Message.Text = "You Selected: <br />"
' Iterate through each item (row) in the DataGrid control and determine
' whether it is selected.
Dim item As DataGridItem
For Each item In ItemsGrid.Items
DetermineSelection(item, count)
Next
' If no items are selected, display the appropriate message.
If count = 0 Then
Message.Text = "Not items selected"
End If
End Sub
Sub DetermineSelection(item As DataGridItem, ByRef count As Integer)
' Retrieve the SelectCheckBox CheckBox control from the specified item (row) in the
' DataGrid control.
Dim selection As CheckBox = CType(item.FindControl("SelectCheckBox"), CheckBox)
' If the item is selected, display the appropriate message and increment the count
' of selected items.
If Not selection Is Nothing Then
If selection.Checked Then
Message.Text &= "- " & item.Cells(1).Text & "<br />"
count = count + 1
End If
End If
End Sub
Sub Selection_Change(sender As Object, e As EventArgs)
' Set the background color for the heading and footer sections of
' the DataGrid control.
ItemsGrid.HeaderStyle.BackColor = System.Drawing.Color.FromName(List.SelectedItem.Value)
ItemsGrid.FooterStyle.BackColor = System.Drawing.Color.FromName(List.SelectedItem.Value)
End Sub
</script>
<head runat="server">
<title>DataGrid HeaderStyle and FooterStyle Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DataGrid HeaderStyle and FooterStyle Example</h3>
Select a backcolor for the header and footer sections.
<br /><br />
<b>Product List</b>
<asp:DataGrid id="ItemsGrid"
BorderColor="black"
BorderWidth="1"
CellPadding="3"
ShowFooter="True"
AutoGenerateColumns="False"
runat="server">
<HeaderStyle BackColor="White">
</HeaderStyle>
<FooterStyle BackColor="White">
</FooterStyle>
<Columns>
<asp:BoundColumn DataField="IntegerValue"
HeaderText="Item"/>
<asp:BoundColumn DataField="StringValue"
HeaderText="Description"/>
<asp:BoundColumn DataField="CurrencyValue"
HeaderText="Price"
DataFormatString="{0:c}">
<ItemStyle HorizontalAlign="Right">
</ItemStyle>
</asp:BoundColumn>
<asp:TemplateColumn HeaderText="Select Item">
<ItemTemplate>
<asp:CheckBox id="SelectCheckBox"
Text="Add to Cart"
Checked="False"
runat="server"/>
</ItemTemplate>
</asp:TemplateColumn>
</Columns>
</asp:DataGrid>
<br /><br />
<asp:Button id="SubmitButton"
Text="Submit"
OnClick = "Button_Click"
runat="server"/>
<br /><br />
<asp:Label id="Message"
runat="server"/>
<hr />
Header and footer backcolor: <br />
<asp:DropDownList id="List"
AutoPostBack="True"
OnSelectedIndexChanged="Selection_Change"
runat="server">
<asp:ListItem Selected="True" Value="White"> White </asp:ListItem>
<asp:ListItem Value="Silver"> Silver </asp:ListItem>
<asp:ListItem Value="DarkGray"> Dark Gray </asp:ListItem>
<asp:ListItem Value="Khaki"> Khaki </asp:ListItem>
<asp:ListItem Value="DarkKhaki"> Dark Khaki </asp:ListItem>
</asp:DropDownList>
</form>
</body>
</html>
Remarks
Use this property to provide a custom style for the heading section of the DataGrid control. Common style attributes that can be adjusted include forecolor, backcolor, font, and content alignment within the cell. Providing a different style enhances the appearance of the DataGrid control.
The HeaderStyle property of the DataGrid control inherits the style settings of the ControlStyle property. For example, if you specify a red font for the ControlStyle property, the HeaderStyle property will also have a red font. This allows you to provide a common appearance for the control by setting a single style property. You can override the inherited style settings by setting the HeaderStyle property. For example, you can specify a blue font for the HeaderStyle property, overriding the red font specified in the ControlStyle property.
To specify a custom style for the heading section, place the <HeaderStyle>
tags between the opening and closing tags of the DataGrid control. You can then list the style attributes within the opening <HeaderStyle>
tag.
Note
The ShowHeader property must be set to true
for this property to be visible.
Applies to
See also
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