GridView.TopPagerRow Eigenschap
Definitie
Belangrijk
Bepaalde informatie heeft betrekking op een voorlopige productversie die aanzienlijk kan worden gewijzigd voordat deze wordt uitgebracht. Microsoft biedt geen enkele expliciete of impliciete garanties met betrekking tot de informatie die hier wordt verstrekt.
Hiermee haalt u een GridViewRow object op dat de bovenste pagerrij in een GridView besturingselement vertegenwoordigt.
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; }[<System.ComponentModel.Browsable(false)>]
member this.TopPagerRow : System.Web.UI.WebControls.GridViewRowPublic Overridable ReadOnly Property TopPagerRow As GridViewRowWaarde van eigenschap
Een GridViewRow die de bovenste pagerrij in het besturingselement vertegenwoordigt.
- Kenmerken
Voorbeelden
In het volgende voorbeeld ziet u hoe u de TopPagerRow eigenschap gebruikt voor toegang tot de bovenste pagerrij in een GridView besturingselement. De TopPagerRow eigenschap wordt gebruikt om een DropDownList besturingselement op te halen uit de paginarij.
<%@ 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>
Opmerkingen
Wanneer pagineering is ingeschakeld (door de AllowPaging eigenschap in te truestellen), wordt automatisch een extra rij met de naam van de pagerrij weergegeven in het GridView besturingselement. De paginarij bevat besturingselementen waarmee de gebruiker naar de andere pagina's kan navigeren en bovenaan, onder of onder aan het besturingselement kan worden weergegeven. Gebruik de TopPagerRow eigenschap om programmatisch toegang te krijgen tot het GridViewRow object dat de bovenste pagerrij in een GridView besturingselement vertegenwoordigt.
Note
De TopPagerRow eigenschap is alleen beschikbaar nadat het GridView besturingselement de bovenste pagerrij in de RowCreated gebeurtenis heeft gemaakt.
Deze eigenschap wordt vaak gebruikt wanneer u de bovenste pagerrij programmatisch moet bewerken, bijvoorbeeld wanneer u aangepaste inhoud toevoegt. Wijzigingen in de TopPagerRow eigenschap moeten worden uitgevoerd nadat het GridView besturingselement is weergegeven. Anders overschrijft het GridView besturingselement eventuele wijzigingen.
