GridView.HeaderRow GridView.HeaderRow GridView.HeaderRow GridView.HeaderRow Property

Definizione

Ottiene un oggetto GridViewRow che rappresenta la riga dell'intestazione in un controllo GridView.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; }
member this.HeaderRow : System.Web.UI.WebControls.GridViewRow
Public Overridable ReadOnly Property HeaderRow As GridViewRow

Valore della proprietà

Un oggetto GridViewRow che rappresenta la riga dell'intestazione in un controllo GridView.A GridViewRow that represents the header row in a GridView control.

Esempi

Nell'esempio seguente viene illustrato come utilizzare la HeaderRow proprietà per modificare a livello di codice il colore del carattere della riga di intestazione in base alla direzione di ordinamento.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>

Commenti

Utilizzare la HeaderRow proprietà per accedere a livello di GridViewRow codice all'oggetto che rappresenta la riga di GridView intestazione in un controllo.Use the HeaderRow property to programmatically access the GridViewRow object that represents the header row in a GridView control.

Nota

La HeaderRow proprietà è disponibile solo dopo che GridView il controllo ha creato RowCreated la riga di intestazione nell'evento.The HeaderRow property is available only after the GridView control creates the header row in the RowCreated event.

Questa proprietà viene comunemente utilizzata quando è necessario modificare a livello di codice la riga di intestazione, ad esempio quando si aggiunge contenuto personalizzato.This property is commonly used when you need to programmatically manipulate the header row, for example, when adding custom content. Qualsiasi modifica alla HeaderRow proprietà deve essere eseguita dopo il rendering GridView del controllo; in caso contrario, il GridView controllo sovrascriverà le modifiche.Any modification to the HeaderRow property must be performed after the GridView control has been rendered; otherwise, the GridView control will overwrite any changes.

Si applica a

Vedi anche