GridViewSortEventArgs.SortDirection Proprietà

  • Riferimento

Definizione

Spazio dei nomi:
System.Web.UI.WebControls
Assembly:
System.Web.dll

Ottiene o imposta la direzione in cui ordinare il controllo GridView.

public:
 property System::Web::UI::WebControls::SortDirection SortDirection { System::Web::UI::WebControls::SortDirection get(); void set(System::Web::UI::WebControls::SortDirection value); };
public System.Web.UI.WebControls.SortDirection SortDirection { get; set; }
member this.SortDirection : System.Web.UI.WebControls.SortDirection with get, set
Public Property SortDirection As SortDirection

Valore della proprietà

SortDirection

Uno dei valori di SortDirection.

Esempio

Nell'esempio seguente viene illustrato come utilizzare la SortDirection proprietà per determinare la direzione in cui ordinare un GridView controllo. Se l'utente tenta di ordinare in ordine decrescente, l'operazione di ordinamento viene annullata.


<%@ 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_Sorting(Object sender, GridViewSortEventArgs e)
  {
    // By default, the sort order toggles when the user clicks 
    // the same sort button repeatedly. For this example, cancel
    // the sort operation if the user attempts to sort in descending
    // order.
    if (e.SortDirection == SortDirection.Descending)
    {
      e.Cancel = true;
      Message.Text = "Sorting in descending order is not supported.";
    }
    else
    {
      Message.Text = "";
    }
  }
  
</script>

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

      <asp:label id="Message"
        forecolor="Red"
        runat="server"/>
                
      <br/>  

      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSource" 
        autogeneratecolumns="true"
        allowpaging="true"
        emptydatatext="No data available." 
        allowsorting="true"
        onsorting="CustomersGridView_Sorting"
        runat="server">
                
      </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_Sorting(ByVal sender As Object, ByVal e As GridViewSortEventArgs)
  
    ' By default, the sort order toggles when the user clicks 
    ' the same sort button repeatedly. For this example, cancel
    ' the sort operation if the user attempts to sort in descending
    ' order.
    If e.SortDirection = SortDirection.Descending Then
    
      e.Cancel = True
      Message.Text = "Sorting in descending order is not supported."
    
    Else
    
      Message.Text = ""
    
    End If
      
  End Sub
  
</script>

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

      <asp:label id="Message"
        forecolor="Red"
        runat="server"/>
                
      <br/>  

      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSource" 
        autogeneratecolumns="true"
        allowpaging="true"
        emptydatatext="No data available." 
        allowsorting="true"
        onsorting="CustomersGridView_Sorting"
        runat="server">
                
      </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

Quando viene generato l'evento Sorting , è possibile utilizzare la SortDirection proprietà per determinare l'ordine in cui il GridView controllo ordina gli elementi (in base all'espressione di ordinamento) quando viene eseguita l'operazione di ordinamento. Poiché l'evento si verifica prima dell'operazione Sorting di ordinamento, è anche possibile utilizzare la SortDirection proprietà per impostare la direzione di ordinamento a livello di codice.

Si applica a

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