Sdílet prostřednictvím

GridViewRowCollection.Count Vlastnost

  • Reference

Definice

Obor názvů:
System.Web.UI.WebControls
Sestavení:
System.Web.dll

Získá počet položek v objektu GridViewRowCollection .

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

Hodnota vlastnosti

Int32

Počet položek v objektu GridViewRowCollection .

Implementuje

Count

Příklady

Následující příklad ukazuje, jak použít Count vlastnost k určení, zda GridView ovládací prvek obsahuje nějaké záznamy. Hodnota větší než nula označuje, že GridView ovládací prvek obsahuje alespoň jeden záznam.


<%@ 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>

Poznámky

Count Pomocí vlastnosti určete počet položek v kolekci. Vlastnost Count se běžně používá při iterování prostřednictvím kolekce k určení horní hranice kolekce. Vlastnost Count se také běžně používá k určení, zda je kolekce prázdná.

Platí pro

Viz také