GridView.Sort(String, SortDirection) Method

Definition

Ordina il controllo GridView in base all'espressione e alla direzione di ordinamento specificate.Sorts the GridView control based on the specified sort expression and direction.

public:
 virtual void Sort(System::String ^ sortExpression, System::Web::UI::WebControls::SortDirection sortDirection);
public virtual void Sort (string sortExpression, System.Web.UI.WebControls.SortDirection sortDirection);
abstract member Sort : string * System.Web.UI.WebControls.SortDirection -> unit
override this.Sort : string * System.Web.UI.WebControls.SortDirection -> unit
Public Overridable Sub Sort (sortExpression As String, sortDirection As SortDirection)

Parameters

sortExpression
String

Espressione di ordinamento in base alla quale ordinare il controllo GridView.The sort expression with which to sort the GridView control.

sortDirection
SortDirection

Uno dei valori SortDirection.One of the SortDirection values.

Exceptions

Il controllo GridView è associato a un controllo origine dati, ma l'oggetto DataSourceView associato all'origine dati è null.The GridView control is bound to a data source control, but the DataSourceView that is associated with the data source is null.

Examples

Nell'esempio seguente viene illustrato come utilizzare il metodo Sort per ordinare il controllo GridView a livello di codice in base a più colonne.The following example demonstrates how to use the Sort method to programmatically sort the GridView control by multiple columns.


<%@ 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 SortButton_Click(Object sender, EventArgs e)
  {

    String expression = "";
    SortDirection direction;

    // Create the sort expression from the values selected 
    // by the user from the DropDownList controls. Multiple
    // columns can be sorted by creating a sort expression
    // that contains a comma-separated list of field names.
    expression = SortList1.SelectedValue + "," + SortList2.SelectedValue;
    
    //  Determine the sort direction. The sort direction
    // applies only to the second column sorted.
    switch (DirectionList.SelectedValue)
    {
      case "Ascending":
        direction = SortDirection.Ascending;
        break;
      case "Descending":
        direction = SortDirection.Descending;
        break;
      default:
        direction = SortDirection.Ascending;
        break;
    }
    
    // Use the Sort method to programmatically sort the GridView
    // control using the sort expression and direction.
    CustomersGridView.Sort(expression, direction);
    
  }
    
</script>

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

      <table>
        <tr>
          <td>
             Sort by:
            <asp:dropdownlist ID="SortList1"
              runat="server">
              <asp:listitem Selected="true">CustomerID</asp:listitem>
              <asp:listitem>CompanyName</asp:listitem>
              <asp:listitem>Address</asp:listitem>
              <asp:listitem>City</asp:listitem>
              <asp:listitem>PostalCode</asp:listitem>
              <asp:listitem>Country</asp:listitem>
            </asp:dropdownlist>
          </td>
          <td colspan="2">
            &nbsp;
          </td>
        </tr>
        <tr>
          <td>
            Then by:
              <asp:dropdownlist ID="SortList2"
                runat="server">
                <asp:listitem Selected="true">CustomerID</asp:listitem>
                <asp:listitem>CompanyName</asp:listitem>
                <asp:listitem>Address</asp:listitem>
                <asp:listitem>City</asp:listitem>
                <asp:listitem>PostalCode</asp:listitem>
                <asp:listitem>Country</asp:listitem>
              </asp:dropdownlist>
          </td>
          <td>
             Sort order:      
          </td>
          <td>
            <asp:radiobuttonlist id="DirectionList"
              runat="server">
              <asp:listitem selected="true">Ascending</asp:listitem>
              <asp:listitem>Descending</asp:listitem>
            </asp:radiobuttonlist>
          </td>
        </tr>
      </table>

      <asp:button id="SortButton"
        text="Sort"
        onclick="SortButton_Click" 
        runat="Server"/>  

      <br/>
      <hr/>
      <br/>

      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSource" 
        autogeneratecolumns="true"
        emptydatatext="No data available." 
        allowpaging="true" 
        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 SortButton_Click(ByVal sender As Object, ByVal e As EventArgs)
    
    Dim expression As String = ""
    Dim direction As SortDirection

    ' Create the sort expression from the values selected 
    ' by the user from the DropDownList controls. Multiple
    ' columns can be sorted by creating a sort expression
    ' that contains a comma-separated list of field names.
    expression = SortList1.SelectedValue & "," & SortList2.SelectedValue
    
    ' Determine the sort direction. The sort direction
    ' applies only to the second column sorted.
    Select Case DirectionList.SelectedValue
    
      Case "Ascending"
        direction = SortDirection.Ascending
      Case "Descending"
        direction = SortDirection.Descending
      Case Else
        direction = SortDirection.Ascending

    End Select
    
    ' Use the Sort method to programmatically sort the GridView
    ' control using the sort expression and direction.
    CustomersGridView.Sort(expression, direction)
    
  End Sub
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView Sort Example</title>
</head>
<body>
    <form id="Form1" runat="server">
        
      <h3>GridView Sort Example</h3>

      <table>
        <tr>
          <td>
             Sort by:
            <asp:dropdownlist ID="SortList1"
              runat="server">
              <asp:listitem Selected="true">CustomerID</asp:listitem>
              <asp:listitem>CompanyName</asp:listitem>
              <asp:listitem>Address</asp:listitem>
              <asp:listitem>City</asp:listitem>
              <asp:listitem>PostalCode</asp:listitem>
              <asp:listitem>Country</asp:listitem>
            </asp:dropdownlist>
          </td>
          <td colspan="2">
            &nbsp;
          </td>
        </tr>
        <tr>
          <td>
            Then by:
              <asp:dropdownlist ID="SortList2"
                runat="server">
                <asp:listitem Selected="true">CustomerID</asp:listitem>
                <asp:listitem>CompanyName</asp:listitem>
                <asp:listitem>Address</asp:listitem>
                <asp:listitem>City</asp:listitem>
                <asp:listitem>PostalCode</asp:listitem>
                <asp:listitem>Country</asp:listitem>
              </asp:dropdownlist>
          </td>
          <td>
             Sort order:      
          </td>
          <td>
            <asp:radiobuttonlist id="DirectionList"
              runat="server">
              <asp:listitem selected="true">Ascending</asp:listitem>
              <asp:listitem>Descending</asp:listitem>
            </asp:radiobuttonlist>
          </td>
        </tr>
      </table>

      <asp:button id="SortButton"
        text="Sort"
        onclick="SortButton_Click" 
        runat="Server"/>  

      <br/>
      <hr/>
      <br/>

      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSource" 
        autogeneratecolumns="true"
        emptydatatext="No data available." 
        allowpaging="true" 
        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>

Remarks

Usare il metodo Sort per ordinare il controllo GridView a livello di codice usando l'espressione e la direzione di ordinamento specificate.Use the Sort method to programmatically sort the GridView control using the specified sort expression and direction. L'espressione di ordinamento specifica la colonna o le colonne con cui eseguire l'ordinamento.The sort expression specifies the column or columns with which to sort. Per ordinare più colonne, creare un'espressione di ordinamento che contenga un elenco delimitato da virgole di nomi di campo.To sort multiple columns, create a sort expression that contains a comma-separated list of field names. La direzione di ordinamento indica se l'ordinamento viene eseguito in ordine crescente o decrescente.The sort direction indicates whether sorting is performed in ascending or descending order. Questo metodo viene comunemente utilizzato quando è necessario ordinare il controllo GridView dall'esterno del controllo, ad esempio da un controllo diverso nella pagina.This method is commonly used when you need to sort the GridView control from outside of the control, such as from a different control on the page. Questo metodo viene comunemente utilizzato anche per impostare a livello di codice un ordinamento predefinito per il controllo GridView al momento del rendering.This method is also commonly used to programmatically set a default sort order for the GridView control when it is first rendered. La chiamata a questo metodo genera anche gli eventi Sorted e Sorting.Calling this method also raises the Sorted and Sorting events.

Applies to

See also