GridView.PageIndexChanging 事件
定义
重要
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在单击某一页导航按钮时，但在 GridView 控件处理分页操作之前发生。
public:
event System::Web::UI::WebControls::GridViewPageEventHandler ^ PageIndexChanging;public event System.Web.UI.WebControls.GridViewPageEventHandler PageIndexChanging;member this.PageIndexChanging : System.Web.UI.WebControls.GridViewPageEventHandler Public Custom Event PageIndexChanging As GridViewPageEventHandler 事件类型
示例
以下示例演示了如果用户尝试在控件处于编辑模式时导航到另一页时GridView，如何使用 PageIndexChanging 事件取消分页操作。
<%@ 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>
注解
当 PageIndexChanging 单击其中一个页导航按钮时，但在控件处理分页操作之前 GridView ，将引发 该事件。 这使你能够提供一个事件处理方法，该方法在发生此事件时执行自定义例程，例如取消分页操作。
备注
以编程方式设置 属性时，不会引发此 PageIndex 事件。
对象 GridViewPageEventArgs 将传递给事件处理方法，该方法使你能够确定用户选择的页面的索引，并指示应取消分页操作。 若要取消分页操作，请将 对象的 属性GridViewPageEventArgs设置为 Canceltrue。
有关如何处理事件的详细信息，请参阅 处理和引发事件。
