GridViewRowCollection.GetEnumerator Metodo

Definizione

Restituisce un enumeratore contenente tutti gli oggetti GridViewRow presenti nell'oggetto GridViewRowCollection.Returns an enumerator that contains all GridViewRow objects in the GridViewRowCollection.

public:
 virtual System::Collections::IEnumerator ^ GetEnumerator();
public System.Collections.IEnumerator GetEnumerator ();
abstract member GetEnumerator : unit -> System.Collections.IEnumerator
override this.GetEnumerator : unit -> System.Collections.IEnumerator
Public Function GetEnumerator () As IEnumerator

Restituisce

Un oggetto implementato IEnumerator contenente tutti gli oggetti GridViewRow presenti nell'oggetto GridViewRowCollection.An IEnumerator implemented object that contains all GridViewRow objects in the GridViewRowCollection.

Implementazioni

Esempi

Nell'esempio seguente viene illustrato come utilizzare il GetEnumerator metodo per recuperare un enumeratore che contiene i valori della raccolta.The following example demonstrates how to use the GetEnumerator method to retrieve an enumerator that contains the values from the collection. L'enumeratore viene iterato e i valori della prima cella vengono visualizzati nella pagina.The enumerator is iterated through and the values of the first cell are displayed on the page.


<%@ 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 AuthorsGridView_RowCreated(Object sender, GridViewRowEventArgs e)
  {
    if (e.Row.RowType == DataControlRowType.Footer)
    {
      Message.Text = "The authors are:<br />";
      
      // Get the enumerator that contains the data rows in the 
      // GridView control.
      IEnumerator rowEnumerator = AuthorsGridView.Rows.GetEnumerator();

      // Iterate though the enumerator and display the value in the
      // first cell of the row.
      while(rowEnumerator.MoveNext())
      {
        GridViewRow row = (GridViewRow)rowEnumerator.Current;
        Message.Text += row.Cells[0].Text + "<br />";
      }
    }
  }

</script>

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

      <table>
        <tr>
          <td>
            <asp:gridview id="AuthorsGridView" 
              datasourceid="AuthorsSqlDataSource" 
              autogeneratecolumns="false"
              onrowcreated="AuthorsGridView_RowCreated"  
              runat="server"> 
                     
              <columns>
                <asp:boundfield datafield="au_lname"
                  headertext="Last Name"/>
                <asp:boundfield datafield="au_fname"
                  headertext="First Name"/>
              </columns>
                                    
            </asp:gridview>
          </td>
          <td>
            <asp:label id="Message" 
              forecolor="Red"
              runat="server"/>
          </td>
        </tr>
      </table>
            
      <!-- This example uses Microsoft SQL Server and connects -->
      <!-- to the Pubs sample database.                        -->
      <asp:sqldatasource id="AuthorsSqlDataSource"  
        selectcommand="SELECT [au_lname], [au_fname] FROM [authors] WHERE [state]='CA'"
        connectionstring="server=localhost;database=pubs;integrated security=SSPI"
        runat="server">
      </asp:sqldatasource>
          
    </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 AuthorsGridView_RowCreated(ByVal sender As Object, ByVal e As GridViewRowEventArgs)

    If e.Row.RowType = DataControlRowType.Footer Then
    
      Message.Text = "The authors are:<br />"
      
      ' Get the enumerator that contains the data rows in the 
      ' GridView control.
      Dim rowEnumerator As IEnumerator = AuthorsGridView.Rows.GetEnumerator()

      ' Iterate though the enumerator and display the value in the
      ' first cell of the row.
      While rowEnumerator.MoveNext()

        Dim row As GridViewRow = CType(rowEnumerator.Current, GridViewRow)
        Message.Text &= row.Cells(0).Text & "<br />"
      
      End While
      
    End If
  
  End Sub

</script>

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

      <table>
        <tr>
          <td>
            <asp:gridview id="AuthorsGridView" 
              datasourceid="AuthorsSqlDataSource" 
              autogeneratecolumns="false"
              onrowcreated="AuthorsGridView_RowCreated"  
              runat="server"> 
                     
              <columns>
                <asp:boundfield datafield="au_lname"
                  headertext="Last Name"/>
                <asp:boundfield datafield="au_fname"
                  headertext="First Name"/>
              </columns>
                                    
            </asp:gridview>
          </td>
          <td>
            <asp:label id="Message" 
              forecolor="Red"
              runat="server"/>
          </td>
        </tr>
      </table>
            
      <!-- This example uses Microsoft SQL Server and connects -->
      <!-- to the Pubs sample database.                        -->
      <asp:sqldatasource id="AuthorsSqlDataSource"  
        selectcommand="SELECT [au_lname], [au_fname] FROM [authors] WHERE [state]='CA'"
        connectionstring="server=localhost;database=pubs;integrated security=SSPI"
        runat="server">
      </asp:sqldatasource>
          
    </form>
  </body>
</html>

Commenti

Utilizzare questo metodo per ottenere un enumeratore che può essere iterato in modo lineare per accedere a ogni elemento GridViewRowCollectionin.Use this method to get an enumerator that can be iterated through linearly to access each item in the GridViewRowCollection. Per accedere all'elemento in corrispondenza della posizione corrente nell'enumeratore, utilizzare IEnumerator.Current la proprietà.To access the item at the current position in the enumerator, use the IEnumerator.Current property. Utilizzare il IEnumerator.MoveNext metodo per passare all'elemento successivo della raccolta.Use the IEnumerator.MoveNext method to move to the next item in the collection. Per spostare l'enumeratore nella posizione iniziale, utilizzare il IEnumerator.Reset metodo.To move the enumerator to its initial position, use the IEnumerator.Reset method.

Nota

Quando si ottiene inizialmente l'enumeratore o si IEnumerator.Reset usa il metodo per spostare l'enumeratore nel primo elemento della raccolta, è necessario chiamare IEnumerator.MoveNext il metodo.When you initially get the enumerator or use the IEnumerator.Reset method to move the enumerator to the first item in the collection, you must call the IEnumerator.MoveNext method. In caso contrario, l'elemento rappresentato dalla IEnumerator.Current proprietà non è definito.Otherwise, the item that is represented by the IEnumerator.Current property is undefined.

Si applica a

Vedi anche