Επεξεργασία

Κοινή χρήση μέσω


GridView.HeaderRow Property

Definition

Gets a GridViewRow object that represents the header row in a GridView control.

public:
 virtual property System::Web::UI::WebControls::GridViewRow ^ HeaderRow { System::Web::UI::WebControls::GridViewRow ^ get(); };
[System.ComponentModel.Browsable(false)]
public virtual System.Web.UI.WebControls.GridViewRow HeaderRow { get; }
[<System.ComponentModel.Browsable(false)>]
member this.HeaderRow : System.Web.UI.WebControls.GridViewRow
Public Overridable ReadOnly Property HeaderRow As GridViewRow

Property Value

A GridViewRow that represents the header row in a GridView control.

Attributes

Examples

The following example demonstrates how to use the HeaderRow property to programmatically change the font color of the header row based on the sort direction.


<%@ 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 CustomersGridView_DataBound(Object sender, EventArgs e)
  {
    
    // Get the header row.
    GridViewRow headerRow = CustomersGridView.HeaderRow;   
    
    // Get the footer row.
    GridViewRow footerRow = CustomersGridView.FooterRow; 

    // Set the font color of the header and footer rows
    // based on the sort direction. 
    switch (CustomersGridView.SortDirection)
    {
      case SortDirection.Ascending:
        headerRow.ForeColor = System.Drawing.Color.Green;
        footerRow.ForeColor = System.Drawing.Color.Green;
        break;
      case SortDirection.Descending:
        headerRow.ForeColor = System.Drawing.Color.Red;
        footerRow.ForeColor = System.Drawing.Color.Red;
        break;
      default:
        headerRow.ForeColor = System.Drawing.Color.Black;
        footerRow.ForeColor = System.Drawing.Color.Black;
        break;
    }

    // Display the sort order in the footer row.
    footerRow.Cells[0].Text = "Sort Order = " + CustomersGridView.SortDirection.ToString();
      
  }
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView HeaderRow and FooterRow Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView HeaderRow and FooterRow Example</h3>

      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSource" 
        autogeneratecolumns="true"
        emptydatatext="No data available." 
        allowsorting="true"
        allowpaging="true" 
        showheader="true"
        showfooter="true"
        ondatabound="CustomersGridView_DataBound"    
        runat="server">
        
        <headerstyle backcolor="LightCyan"
          forecolor="MediumBlue"/>
                    
        <footerstyle backcolor="LightCyan"
          forecolor="MediumBlue"/>
                        
      </asp:gridview>
            
      <!-- This example uses Microsoft SQL Server and connects  -->
      <!-- to the Northwind sample database. Use an ASP.NET     -->
      <!-- expression to retrieve the connection string value   -->
      <!-- from the Web.config file.                            -->
      <asp:sqldatasource id="CustomersSource"
        selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>
        
    </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 CustomersGridView_DataBound(ByVal sender As Object, ByVal e As EventArgs)
      
    ' Get the header row.
    Dim headerRow As GridViewRow = CustomersGridView.HeaderRow
    
    ' Get the footer row.
    Dim footerRow As GridViewRow = CustomersGridView.FooterRow

    ' Set the font color of the header and footer rows
    ' based on the sort direction. 
    Select Case CustomersGridView.SortDirection

      Case SortDirection.Ascending
        headerRow.ForeColor = System.Drawing.Color.Green
        footerRow.ForeColor = System.Drawing.Color.Green
      Case SortDirection.Descending
        headerRow.ForeColor = System.Drawing.Color.Red
        footerRow.ForeColor = System.Drawing.Color.Red
      Case Else
        headerRow.ForeColor = System.Drawing.Color.Black
        footerRow.ForeColor = System.Drawing.Color.Black
        
    End Select

    ' Display the sort order in the footer row.
    footerRow.Cells(0).Text = "Sort Order = " & CustomersGridView.SortDirection.ToString()
      
  End Sub
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView HeaderRow and FooterRow Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView HeaderRow and FooterRow Example</h3>

      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSource" 
        autogeneratecolumns="true"
        emptydatatext="No data available." 
        allowsorting="true"
        allowpaging="true" 
        showheader="true"
        showfooter="true"
        ondatabound="CustomersGridView_DataBound"    
        runat="server">
        
        <headerstyle backcolor="LightCyan"
          forecolor="MediumBlue"/>
                    
        <footerstyle backcolor="LightCyan"
          forecolor="MediumBlue"/>
                        
      </asp:gridview>
            
      <!-- This example uses Microsoft SQL Server and connects  -->
      <!-- to the Northwind sample database. Use an ASP.NET     -->
      <!-- expression to retrieve the connection string value   -->
      <!-- from the Web.config file.                            -->
      <asp:sqldatasource id="CustomersSource"
        selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>
        
    </form>
  </body>
</html>

Remarks

Use the HeaderRow property to programmatically access the GridViewRow object that represents the header row in a GridView control.

Note

The HeaderRow property is available only after the GridView control creates the header row in the RowCreated event.

This property is commonly used when you need to programmatically manipulate the header row, for example, when adding custom content. Any modification to the HeaderRow property must be performed after the GridView control has been rendered; otherwise, the GridView control will overwrite any changes.

Applies to

See also