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GridView.PageIndex Property

Definition

Gets or sets the index of the currently displayed page.

public:
 virtual property int PageIndex { int get(); void set(int value); };
[System.ComponentModel.Browsable(true)]
public virtual int PageIndex { get; set; }
[<System.ComponentModel.Browsable(true)>]
member this.PageIndex : int with get, set
Public Overridable Property PageIndex As Integer

Property Value

The zero-based index of the currently displayed page.

Attributes

Exceptions

The PageIndex property is set to a value less than 0.

Examples

The following example demonstrates how to use the PageIndex property to determine the index of the currently displayed page in the GridView control. The example also shows how the PageIndex property can be used to specify which page is displayed after the user selects a value 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">

  protected void PageDropDownList_SelectedIndexChanged(Object sender, EventArgs e)
  {

    // Retrieve the pager row.
    GridViewRow pagerRow = CustomersGridView.BottomPagerRow;
    
    // Retrieve the PageDropDownList DropDownList from the bottom 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;

  }

  protected void CustomersGridView_DataBound(Object sender, EventArgs e)
  {

    // Retrieve the pager row.
    GridViewRow pagerRow = CustomersGridView.BottomPagerRow;
    
    // 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 PagerTemplate Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView PagerTemplate Example</h3>

      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSqlDataSource"   
        autogeneratecolumns="true"
        allowpaging="true"
        ondatabound="CustomersGridView_DataBound"  
        runat="server">
              
        <pagerstyle forecolor="Blue"
          backcolor="LightBlue"/>
              
        <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%; text-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">

    Protected Sub PageDropDownList_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs)
    
        ' Retrieve the pager row.
        Dim pagerRow As GridViewRow = CustomersGridView.BottomPagerRow
    
        ' 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
    
    Protected Sub CustomersGridView_DataBound(ByVal sender As Object, ByVal e As EventArgs)
    
        ' Retrieve the pager row.
        Dim pagerRow As GridViewRow = CustomersGridView.BottomPagerRow
    
        ' 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 PagerTemplate Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView PagerTemplate Example</h3>

      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSqlDataSource"   
        autogeneratecolumns="true"
        allowpaging="true"
        ondatabound="CustomersGridView_DataBound"  
        runat="server">
              
        <pagerstyle forecolor="Blue"
          backcolor="LightBlue"/>
              
        <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%; text-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>

Remarks

When the paging feature is enabled (by setting the AllowPaging property to true), use the PageIndex property to determine the index of the currently displayed page. You can also use this property to programmatically change the displayed page.

Applies to

See also