ערוך

שתף באמצעות

GridViewPageEventArgs.NewPageIndex Property

  • Reference

Definition

Namespace:
System.Web.UI.WebControls
Assembly:
System.Web.dll

Gets or sets the index of the new page to display in the GridView control.

public:
 property int NewPageIndex { int get(); void set(int value); };
public int NewPageIndex { get; set; }
member this.NewPageIndex : int with get, set
Public Property NewPageIndex As Integer

Property Value

Int32

The index of the new page to display in the GridView control.

Exceptions

ArgumentOutOfRangeException

The NewPageIndex property is less than zero.

Examples

The following example demonstrates how to use the NewPageIndex property to determine the index of the page selected by the user.


<%@ 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 CustomersGridView_PageIndexChanging(Object sender, GridViewPageEventArgs e)
  {
    
    // Cancel the paging operation if the user attempts to navigate
    // to another page while the GridView control is in edit mode. 
    if (CustomersGridView.EditIndex != -1)
    {
      // Use the Cancel property to cancel the paging operation.
      e.Cancel = true;
      
      // Display an error message.
      int newPageNumber = e.NewPageIndex + 1;
      Message.Text = "Please update the record before moving to page " +
        newPageNumber.ToString() + ".";
    }
    else
    {
      // Clear the error message.
      Message.Text = "";
    }
    
  }

  void CustomersGridView_RowCancelingEdit(Object sender, GridViewCancelEditEventArgs e)
  {
    // Clear the error message.
    Message.Text = "";
  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView PageIndexChanging Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView PageIndexChanging Example</h3>
            
      <asp:label id="Message"
        forecolor="Red"
        runat="server"/>
                
      <br/>  

      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSource" 
        autogeneratecolumns="true"
        emptydatatext="No data available." 
        allowpaging="true"
        autogenerateeditbutton="true"
        datakeynames="CustomerID"  
        onpageindexchanging="CustomersGridView_PageIndexChanging"
        onrowcancelingedit="CustomersGridView_RowCancelingEdit" 
        runat="server">
                
        <pagersettings mode="Numeric"
          position="Bottom"           
          pagebuttoncount="10"/>
                      
        <pagerstyle backcolor="LightBlue"/>
                
      </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="CustomersSource"
        selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        updatecommand="Update Customers SET CompanyName=@CompanyName, Address=@Address, City=@City, PostalCode=@PostalCode, Country=@Country WHERE (CustomerID = @CustomerID)"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>
            
    </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 CustomersGridView_PageIndexChanging(ByVal sender As Object, ByVal e As GridViewPageEventArgs)
    
    ' Cancel the paging operation if the user attempts to navigate
    ' to another page while the GridView control is in edit mode. 
    If CustomersGridView.EditIndex <> -1 Then
    
      ' Use the Cancel property to cancel the paging operation.
      e.Cancel = True
      
      ' Display an error message.
      Dim newPageNumber As Integer = e.NewPageIndex + 1
      Message.Text = "Please update the record before moving to page " & _
        newPageNumber.ToString() & "."
    
    Else
    
      ' Clear the error message.
      Message.Text = ""
    
    End If
    
  End Sub

  Sub CustomersGridView_RowCancelingEdit(ByVal sender As Object, ByVal e As GridViewCancelEditEventArgs)
  
    ' Clear the error message.
    Message.Text = ""
    
  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView PageIndexChanging Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView PageIndexChanging Example</h3>
            
      <asp:label id="Message"
        forecolor="Red"
        runat="server"/>
                
      <br/>  

      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSource" 
        autogeneratecolumns="true"
        emptydatatext="No data available." 
        allowpaging="true"
        autogenerateeditbutton="true"
        datakeynames="CustomerID"  
        onpageindexchanging="CustomersGridView_PageIndexChanging"
        onrowcancelingedit="CustomersGridView_RowCancelingEdit" 
        runat="server">
                
        <pagersettings mode="Numeric"
          position="Bottom"           
          pagebuttoncount="10"/>
                      
        <pagerstyle backcolor="LightBlue"/>
                
      </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="CustomersSource"
        selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        updatecommand="Update Customers SET CompanyName=@CompanyName, Address=@Address, City=@City, PostalCode=@PostalCode, Country=@Country WHERE (CustomerID = @CustomerID)"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>
            
    </form>
  </body>
</html>

Remarks

Because the PageIndexChanging event occurs before the GridView control performs the paging operation, the PageIndex property of the control cannot be used to determine the index of the page selected by the user. Use the NewPageIndex property to determine the index of the page selected by the user.

Note

During the PageIndexChanging event, the PageIndex property still contains the index of the previously displayed page.

You can also use this property to programmatically override the page index selected by the user by setting it to another value.

Applies to

See also