GridView.TopPagerRow Proprietà

Definizione

Ottiene un oggetto GridViewRow che rappresenta la riga di spostamento superiore in un controllo GridView.Gets a GridViewRow object that represents the top pager row in a GridView control.

public:
 virtual property System::Web::UI::WebControls::GridViewRow ^ TopPagerRow { System::Web::UI::WebControls::GridViewRow ^ get(); };
[System.ComponentModel.Browsable(false)]
public virtual System.Web.UI.WebControls.GridViewRow TopPagerRow { get; }
member this.TopPagerRow : System.Web.UI.WebControls.GridViewRow
Public Overridable ReadOnly Property TopPagerRow As GridViewRow

Valore della proprietà

Un oggetto GridViewRow che rappresenta la riga di spostamento superiore nel controllo.A GridViewRow that represents the top pager row in the control.

Attributi

Esempi

Nell'esempio seguente viene illustrato come utilizzare la TopPagerRow proprietà per accedere alla riga del pager superiore in GridView un controllo.The following example demonstrates how to use the TopPagerRow property to access the top pager row in a GridView control. La TopPagerRow proprietà viene utilizzata per recuperare un DropDownList controllo dalla riga di cercapersone.The TopPagerRow property is used to retrieve a DropDownList control from the pager row.


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

    // Retrieve the pager row.
    GridViewRow pagerRow = CustomersGridView.TopPagerRow;
   
    // Retrieve the PageDropDownList DropDownList from the pager row.
    DropDownList pageList = (DropDownList)pagerRow.Cells[0].FindControl("PageDropDownList");

    // Set the PageIndex property to display that page selected by the user.
    CustomersGridView.PageIndex = pageList.SelectedIndex;

  }

  void CustomersGridView_DataBound(Object sender, EventArgs e)
  {
    
    // Retrieve the PagerRow.
    GridViewRow pagerRow = CustomersGridView.TopPagerRow;
    
    // Retrieve the DropDownList and Label controls from the row.
    DropDownList pageList = (DropDownList)pagerRow.Cells[0].FindControl("PageDropDownList");
    Label pageLabel = (Label)pagerRow.Cells[0].FindControl("CurrentPageLabel");
        
    if(pageList != null)
    {
        
      // Create the values for the DropDownList control based on 
      // the  total number of pages required to display the data
      // source.
      for(int i=0; i<CustomersGridView.PageCount; i++)
      {
            
        // Create a ListItem object to represent a page.
        int pageNumber = i + 1;
        ListItem item = new ListItem(pageNumber.ToString());         
            
        // If the ListItem object matches the currently selected
        // page, flag the ListItem object as being selected. Because
        // the DropDownList control is recreated each time the pager
        // row gets created, this will persist the selected item in
        // the DropDownList control.   
        if(i==CustomersGridView.PageIndex)
        {
          item.Selected = true;
        }
            
        // Add the ListItem object to the Items collection of the 
        // DropDownList.
        pageList.Items.Add(item);
                
      }
        
    }
        
    if(pageLabel != null)
    {
        
      // Calculate the current page number.
      int currentPage = CustomersGridView.PageIndex + 1;     
        
      // Update the Label control with the current page information.
      pageLabel.Text = "Page " + currentPage.ToString() +
        " of " + CustomersGridView.PageCount.ToString();
        
    }    
    
  }

</script>

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

      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSqlDataSource"   
        autogeneratecolumns="true"
        allowpaging="true"
        ondatabound="CustomersGridView_DataBound"  
        runat="server">
              
        <pagerstyle forecolor="Blue"
          backcolor="LightBlue"/>
          
        <pagersettings position="Top"/>
              
        <pagertemplate>
          
          <table width="100%">                    
            <tr>                        
              <td style="width:70%">
                          
                <asp:label id="MessageLabel"
                  forecolor="Blue"
                  text="Select a page:" 
                  runat="server"/>
                <asp:dropdownlist id="PageDropDownList"
                  autopostback="true"
                  onselectedindexchanged="PageDropDownList_SelectedIndexChanged" 
                  runat="server"/>
                      
              </td>   
                      
              <td style="width:70%" align="right">
                      
                <asp:label id="CurrentPageLabel"
                  forecolor="Blue"
                  runat="server"/>
                      
              </td>
                                            
            </tr>                    
          </table>
          
        </pagertemplate> 
          
      </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="CustomersSqlDataSource"  
        selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
        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 PageDropDownList_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs)
    
    ' Retrieve the pager row.
    Dim pagerRow As GridViewRow = CustomersGridView.TopPagerRow
    
    ' Retrieve the PageDropDownList DropDownList from the bottom pager row.
    Dim pageList As DropDownList = CType(pagerRow.Cells(0).FindControl("PageDropDownList"), DropDownList)
        
    ' Set the PageIndex property to display that page selected by the user.
    CustomersGridView.PageIndex = pageList.SelectedIndex
    
  End Sub
    
  Sub CustomersGridView_DataBound(ByVal sender As Object, ByVal e As EventArgs)
    
    ' Get the PagerRow.
    Dim pagerRow As GridViewRow = CustomersGridView.TopPagerRow
    
    ' Retrieve the DropDownList and Label controls from the row.
    Dim pageList As DropDownList = CType(pagerRow.Cells(0).FindControl("PageDropDownList"), DropDownList)
    Dim pageLabel As Label = CType(pagerRow.Cells(0).FindControl("CurrentPageLabel"), Label)
        
    If Not pageList Is Nothing Then
        
      ' Create the values for the DropDownList control based on 
      ' the  total number of pages required to display the data
      ' source.
      Dim i As Integer
            
      For i = 0 To CustomersGridView.PageCount - 1
            
        ' Create a ListItem object to represent a page.
        Dim pageNumber As Integer = i + 1
        Dim item As ListItem = New ListItem(pageNumber.ToString())
            
        ' If the ListItem object matches the currently selected
        ' page, flag the ListItem object as being selected. Because
        ' the DropDownList control is recreated each time the pager
        ' row gets created, this will persist the selected item in
        ' the DropDownList control.   
        If i = CustomersGridView.PageIndex Then
          
          item.Selected = True
                
        End If
            
        ' Add the ListItem object to the Items collection of the 
        ' DropDownList.
        pageList.Items.Add(item)
                
      Next i
        
    End If
        
    If Not pageLabel Is Nothing Then
        
      ' Calculate the current page number.
      Dim currentPage As Integer = CustomersGridView.PageIndex + 1
        
      ' Update the Label control with the current page information.
      pageLabel.Text = "Page " & currentPage.ToString() & _
          " of " & CustomersGridView.PageCount.ToString()
        
    End If
    
  End Sub

</script>

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

      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSqlDataSource"   
        autogeneratecolumns="true"
        allowpaging="true"
        ondatabound="CustomersGridView_DataBound"  
        runat="server">
              
        <pagerstyle forecolor="Blue"
          backcolor="LightBlue"/>
          
        <pagersettings position="Top"/>
              
        <pagertemplate>
          
          <table width="100%">                    
            <tr>                        
              <td style="width:70%">
                          
                <asp:label id="MessageLabel"
                  forecolor="Blue"
                  text="Select a page:" 
                  runat="server"/>
                <asp:dropdownlist id="PageDropDownList"
                  autopostback="true"
                  onselectedindexchanged="PageDropDownList_SelectedIndexChanged" 
                  runat="server"/>
                      
              </td>   
                      
              <td style="width:70%" align="right">
                      
                <asp:label id="CurrentPageLabel"
                  forecolor="Blue"
                  runat="server"/>
                      
              </td>
                                            
            </tr>                    
          </table>
          
        </pagertemplate> 
          
      </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="CustomersSqlDataSource"  
        selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
        runat="server">
      </asp:sqldatasource>
            
    </form>
  </body>
</html>

Commenti

Quando il paging è abilitato, impostando AllowPaging la proprietà truesu, GridView viene visualizzata automaticamente nel controllo una riga aggiuntiva denominata riga di spostamento.When paging is enabled (by setting the AllowPaging property to true), an additional row called the pager row is automatically displayed in the GridView control. La riga del pager contiene controlli che consentono all'utente di passare alle altre pagine e possono essere visualizzate nella parte superiore, in basso o nella parte superiore e inferiore del controllo.The pager row contains controls that allow the user to navigate to the other pages and can be displayed at the top, the bottom, or both the top and bottom of the control. Utilizzare la TopPagerRow proprietà per accedere a livello di GridViewRow codice all'oggetto che rappresenta la riga di spostamento GridView superiore in un controllo.Use the TopPagerRow property to programmatically access the GridViewRow object that represents the top pager row in a GridView control.

Nota

La TopPagerRow proprietà è disponibile solo dopo che GridView il controllo ha creato la riga di spostamento RowCreated superiore nell'evento.The TopPagerRow property is available only after the GridView control creates the top pager row in the RowCreated event.

Questa proprietà viene comunemente utilizzata quando è necessario modificare a livello di codice la riga del pager superiore, ad esempio quando si aggiunge contenuto personalizzato.This property is commonly used when you need to programmatically manipulate the top pager row, for example when adding custom content. Qualsiasi modifica alla TopPagerRow proprietà deve essere eseguita dopo il rendering GridView del controllo; in caso contrario, il GridView controllo sovrascriverà le modifiche.Any modification to the TopPagerRow property must be performed after the GridView control has been rendered; otherwise, the GridView control will overwrite any changes.

Si applica a

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