GridViewRowCollection.Count GridViewRowCollection.Count GridViewRowCollection.Count GridViewRowCollection.Count Property

定義

GridViewRowCollection オブジェクト内の項目の数を取得します。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

プロパティ値

GridViewRowCollection オブジェクト内の項目の数。The number of items in the GridViewRowCollection object.

実装

次の例では、 Countプロパティを使用して、 GridViewコントロールにレコードが含まれているかどうかを確認する方法を示します。The following example demonstrates how to use the Count property to determine whether the GridView control contains any records. 0より大きい値は、コントロールにGridView少なくとも1つのレコードが含まれていることを示します。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>

注釈

コレクション内Countの項目の数を確認するには、プロパティを使用します。Use the Count property to determine the number of items in the collection. Countプロパティは、コレクションの上限を決定するためにコレクションを反復処理するときによく使用されます。The Count property is commonly used when iterating through the collection to determine the upper bound of the collection. またCount 、プロパティは、コレクションが空であるかどうかを判断するためにも使用されます。The Count property is also commonly used to determine whether a collection is empty.

適用対象

こちらもご覧ください