GridViewRowCollection.Count Proprietà

Definizione

Ottiene il numero di elementi nell'oggetto GridViewRowCollection.Gets the number of items in the GridViewRowCollection object.

public:
 property int Count { int get(); };
public int Count { get; }
member this.Count : int
Public ReadOnly Property Count As Integer

Valore della proprietà

Il numero di elementi nell'oggetto GridViewRowCollection.The number of items in the GridViewRowCollection object.

Implementazioni

Esempi

Nell'esempio seguente viene illustrato come utilizzare la Count proprietà per determinare se il GridView controllo contiene record.The following example demonstrates how to use the Count property to determine whether the GridView control contains any records. Un valore maggiore di zero indica che il GridView controllo contiene almeno un record.A value greater than zero indicates that the GridView control contains at least one record.


<%@ 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)
    {      
      
      // Get the number of items in the Rows collection.
      int count = AuthorsGridView.Rows.Count;

      // If the GridView control contains any records, display 
      // the last name of each author in the GridView control.
      if (count > 0)
      {      
        Message.Text = "The authors are:<br />";
        
        foreach (GridViewRow row in AuthorsGridView.Rows)
        {
          Message.Text += row.Cells[0].Text + "<br />";
        }
      }
      
    }
  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridViewRowCollection Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridViewRowCollection 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
      
      ' Get the number of items in the Rows collection.
      Dim count As Integer = AuthorsGridView.Rows.Count

      ' If the GridView control contains any records, display 
      ' the last name of each author in the GridView control.
      If count > 0 Then
           
        Message.Text = "The authors are:<br />"
        
        Dim row As GridViewRow
        For Each row In AuthorsGridView.Rows
        
          Message.Text &= row.Cells(0).Text & "<br />"
        
        Next
        
      End If
        
    End If
        
  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridViewRowCollection Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridViewRowCollection 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 la Count proprietà per determinare il numero di elementi nella raccolta.Use the Count property to determine the number of items in the collection. La Count proprietà viene comunemente utilizzata quando si scorre la raccolta per determinare il limite superiore della raccolta.The Count property is commonly used when iterating through the collection to determine the upper bound of the collection. La Count proprietà viene utilizzata comunemente anche per determinare se una raccolta è vuota.The Count property is also commonly used to determine whether a collection is empty.

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