DataGridPageChangedEventHandler Delegát
Definice
Důležité
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Představuje metodu, která zpracovává PageIndexChanged událost DataGrid ovládacího prvku.
public delegate void DataGridPageChangedEventHandler(System::Object ^ source, DataGridPageChangedEventArgs ^ e);public delegate void DataGridPageChangedEventHandler(object source, DataGridPageChangedEventArgs e);type DataGridPageChangedEventHandler = delegate of obj * DataGridPageChangedEventArgs -> unitPublic Delegate Sub DataGridPageChangedEventHandler(source As Object, e As DataGridPageChangedEventArgs)Parametry
- source
- Object
Zdroj události
A DataGridPageChangedEventArgs , který obsahuje data události.
Příklady
Následující příklad kódu ukazuje, jak zadat a kód obslužné rutiny PageIndexChanged pro událost. Zobrazí stránky DataGrid ovládacího prvku v přírůstcích po 10 položkách.
<%@ Page Language="C#" %>
<%@ Import Namespace="System.Data" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
private ICollection CreateDataSource()
{
// Create sample data for the DataGrid control.
DataTable dt = new DataTable();
DataRow dr;
// Define the columns of the table.
dt.Columns.Add(new DataColumn("IntegerValue", typeof(Int32)));
dt.Columns.Add(new DataColumn("StringValue", typeof(String)));
dt.Columns.Add(new DataColumn("CurrencyValue", typeof(Double)));
// Populate the table with sample values.
for (int i = 0; i <= 100; i++)
{
dr = dt.NewRow();
dr[0] = i;
dr[1] = "Item " + i.ToString();
dr[2] = 1.23 * (i + 1);
dt.Rows.Add(dr);
}
DataView dv = new DataView(dt);
return dv;
}
private void Page_Load(Object sender, EventArgs e)
{
// Load sample data only once, when the page is first loaded.
if (!IsPostBack)
{
ItemsGrid.DataSource = CreateDataSource();
ItemsGrid.DataBind();
}
}
private void Check_Change(Object sender, EventArgs e)
{
// Allow or prevent paging depending
// on the user's selection.
ItemsGrid.AllowPaging = AllowPagingCheckBox.Checked;
// Rebind the data to refresh the DataGrid control.
ItemsGrid.DataSource = CreateDataSource();
ItemsGrid.DataBind();
}
private void Grid_Change(Object sender, DataGridPageChangedEventArgs e)
{
// For the DataGrid control to navigate to the correct page when
// paging is allowed, the CurrentPageIndex property must be updated
// programmatically. This process is usually accomplished in the
// event-handling method for the PageIndexChanged event.
// Set CurrentPageIndex to the page the user clicked.
ItemsGrid.CurrentPageIndex = e.NewPageIndex;
// Rebind the data to refresh the DataGrid control.
ItemsGrid.DataSource = CreateDataSource();
ItemsGrid.DataBind();
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
<title>DataGrid AllowPaging Example</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<h3>DataGrid AllowPaging Example</h3>
<p>Select whether to allow paging in the DataGrid control.<br />
<asp:CheckBox id="AllowPagingCheckBox"
Text="Allow paging"
AutoPostBack="True"
Checked="True"
OnCheckedChanged="Check_Change"
runat="server" />
</p>
<hr />
<asp:Label runat="server"
AssociatedControlID="ItemsGrid"
Font-Bold="true">Product List</asp:Label>
<asp:DataGrid id="ItemsGrid" runat="server"
BorderColor="Gray"
BorderWidth="1"
CellPadding="3"
AutoGenerateColumns="False"
UseAccessibleHeader="true"
PageSize="10"
AllowPaging="True"
OnPageIndexChanged="Grid_Change">
<HeaderStyle BackColor="LightBlue" />
<Columns>
<asp:BoundColumn DataField="IntegerValue"
SortExpression="IntegerValue"
ItemStyle-HorizontalAlign="center"
HeaderText="Item" />
<asp:BoundColumn DataField="StringValue"
HeaderText="Description"
ItemStyle-HorizontalAlign="left"
SortExpression="StringValue" />
<asp:BoundColumn DataField="CurrencyValue"
HeaderText="Price"
SortExpression="CurrencyValue"
DataFormatString="{0:c}" />
</Columns>
<ItemStyle HorizontalAlign="Right" />
</asp:DataGrid>
</div>
</form>
</body>
</html>
<%@ Page Language="VB" %>
<%@ Import Namespace="System.Data" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
Function CreateDataSource() As ICollection
' Create sample data for the DataGrid control.
Dim dt As DataTable = New DataTable()
Dim dr As DataRow
' Define the columns of the table.
dt.Columns.Add(New DataColumn("IntegerValue", GetType(Int32)))
dt.Columns.Add(New DataColumn("StringValue", GetType(String)))
dt.Columns.Add(New DataColumn("CurrencyValue", GetType(Double)))
' Populate the table with sample values.
Dim i As Integer
For i = 0 To 100
dr = dt.NewRow()
dr(0) = i
dr(1) = "Item " & i.ToString()
dr(2) = 1.23 * (i + 1)
dt.Rows.Add(dr)
Next i
Dim dv As DataView = New DataView(dt)
Return dv
End Function
Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
' Load sample data only once, when the page is first loaded.
If Not IsPostBack Then
ItemsGrid.DataSource = CreateDataSource()
ItemsGrid.DataBind()
End If
End Sub
Sub Check_Change(ByVal sender As Object, ByVal e As EventArgs)
' Allow or prevent paging depending on the user's selection.
ItemsGrid.AllowPaging = AllowPagingCheckBox.Checked()
' Rebind the data to refresh the DataGrid control.
ItemsGrid.DataSource = CreateDataSource()
ItemsGrid.DataBind()
End Sub
Sub Grid_Change(ByVal sender As Object, ByVal e As DataGridPageChangedEventArgs)
' For the DataGrid control to navigate to the correct page when
' paging is allowed, the CurrentPageIndex property must be updated
' programmatically. This process is usually accomplished in the
' event-handling method for the PageIndexChanged event.
' Set CurrentPageIndex to the page the user clicked.
ItemsGrid.CurrentPageIndex = e.NewPageIndex
' Rebind the data to refresh the DataGrid control.
ItemsGrid.DataSource = CreateDataSource()
ItemsGrid.DataBind()
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head2" runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<div>
<h3>DataGrid AllowPaging Example</h3>
<p>Select whether to allow paging in the DataGrid control.<br />
<asp:CheckBox id="AllowPagingCheckBox"
Text="Allow paging"
AutoPostBack="True"
Checked="True"
OnCheckedChanged="Check_Change"
runat="server" />
</p>
<hr />
<asp:Label ID="Label1" runat="server"
AssociatedControlID="ItemsGrid"
Font-Bold="true">Product List</asp:Label>
<asp:DataGrid id="ItemsGrid" runat="server"
BorderColor="Gray"
BorderWidth="1"
CellPadding="3"
UseAccessibleHeader="true"
AutoGenerateColumns="False"
PageSize="10"
AllowPaging="True"
OnPageIndexChanged="Grid_Change">
<HeaderStyle BackColor="LightBlue" />
<Columns>
<asp:BoundColumn DataField="IntegerValue"
SortExpression="IntegerValue"
ItemStyle-HorizontalAlign="center"
HeaderText="Item" />
<asp:BoundColumn DataField="StringValue"
HeaderText="Description"
ItemStyle-HorizontalAlign="left"
SortExpression="StringValue" />
<asp:BoundColumn DataField="CurrencyValue"
HeaderText="Price"
SortExpression="CurrencyValue"
DataFormatString="{0:c}" />
</Columns>
<ItemStyle HorizontalAlign="Right" />
</asp:DataGrid>
</div>
</form>
</body>
</html>
<%@ Page Language="C#" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<script runat="server">
ICollection CreateDataSource()
{
// Create sample data for the DataGrid control.
DataTable dt = new DataTable();
DataRow dr;
// Define the columns of the table.
dt.Columns.Add(new DataColumn("IntegerValue", typeof(Int32)));
dt.Columns.Add(new DataColumn("StringValue", typeof(String)));
dt.Columns.Add(new DataColumn("CurrencyValue", typeof(Double)));
// Populate the table with sample values.
for (int i=0; i<=100; i++)
{
dr = dt.NewRow();
dr[0] = i;
dr[1] = "Item " + i.ToString();
dr[2] = 1.23 * (i + 1);
dt.Rows.Add(dr);
}
DataView dv = new DataView(dt);
return dv;
}
void Page_Load(Object sender, EventArgs e)
{
// Load sample data only once, when the page is first loaded.
if (!IsPostBack)
{
ItemsGrid.DataSource = CreateDataSource();
ItemsGrid.DataBind();
}
// Manually register the event-handling method for the PageIndexChanged
// event of the DataGrid control.
ItemsGrid.PageIndexChanged += new DataGridPageChangedEventHandler(this.Grid_Change);
}
void Check_Change(Object sender, EventArgs e)
{
// Allow or prevent paging depending on the user's selection.
if (AllowPagingCheckBox.Checked)
{
ItemsGrid.AllowPaging = true;
}
else
{
ItemsGrid.AllowPaging = false;
}
// Re-bind the data to refresh the DataGrid control.
ItemsGrid.DataSource = CreateDataSource();
ItemsGrid.DataBind();
}
void Grid_Change(Object sender, DataGridPageChangedEventArgs e)
{
// For the DataGrid control to navigate to the correct page when paging is
// allowed, the CurrentPageIndex property must be programmatically updated.
// This process is usually accomplished in the event-handling method for the
// PageIndexChanged event.
// Set CurrentPageIndex to the page the user clicked.
ItemsGrid.CurrentPageIndex = e.NewPageIndex;
// Re-bind the data to refresh the DataGrid control.
ItemsGrid.DataSource = CreateDataSource();
ItemsGrid.DataBind();
}
</script>
<head runat="server">
<title>DataGrid PageIndexChanged Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DataGrid PageIndexChanged Example</h3>
Select whether to allow paging in the DataGrid control.
<br /><br />
<b>Product List</b>
<asp:DataGrid id="ItemsGrid"
BorderColor="black"
BorderWidth="1"
CellPadding="3"
AutoGenerateColumns="False"
PageSize="10"
AllowPaging="True"
runat="server">
<HeaderStyle BackColor="#00aaaa">
</HeaderStyle>
<Columns>
<asp:BoundColumn DataField="IntegerValue"
SortExpression="IntegerValue"
HeaderText="Item"/>
<asp:BoundColumn DataField="StringValue"
SortExpression="StringValue"
HeaderText="Description"/>
<asp:BoundColumn DataField="CurrencyValue"
HeaderText="Price"
SortExpression="CurrencyValue"
DataFormatString="{0:c}">
<ItemStyle HorizontalAlign="Right">
</ItemStyle>
</asp:BoundColumn>
</Columns>
</asp:DataGrid>
<hr />
<table cellpadding="5">
<tr>
<td>
<asp:CheckBox id="AllowPagingCheckBox"
Text="Allow paging"
AutoPostBack="True"
Checked="True"
OnCheckedChanged="Check_Change"
runat="server"/>
</td>
</tr>
</table>
</form>
</body>
</html>
<%@ Page Language="VB" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<script runat="server">
Function CreateDataSource() As ICollection
' Create sample data for the DataGrid control.
Dim dt As DataTable = New DataTable()
Dim dr As DataRow
' Define the columns of the table.
dt.Columns.Add(new DataColumn("IntegerValue", GetType(Int32)))
dt.Columns.Add(new DataColumn("StringValue", GetType(String)))
dt.Columns.Add(new DataColumn("CurrencyValue", GetType(Double)))
' Populate the table with sample values.
Dim i As Integer
For i=0 To 100
dr = dt.NewRow()
dr(0) = i
dr(1) = "Item " & i.ToString()
dr(2) = 1.23 * (i + 1)
dt.Rows.Add(dr)
Next i
Dim dv As DataView = New DataView(dt)
Return dv
End Function
Sub Page_Load(sender As Object, e As EventArgs)
' Load sample data only once, when the page is first loaded.
If Not IsPostBack Then
ItemsGrid.DataSource = CreateDataSource()
ItemsGrid.DataBind()
End If
' Manually register the event-handling method for the PageIndexChanged
' event of the DataGrid control.
AddHandler ItemsGrid.PageIndexChanged, AddressOf Grid_Change
End Sub
Sub Check_Change(sender As Object, e As EventArgs)
' Allow or prevent paging depending on the user's selection.
If AllowPagingCheckBox.Checked Then
ItemsGrid.AllowPaging = True
Else
ItemsGrid.AllowPaging = False
End If
' Re-bind the data to refresh the DataGrid control.
ItemsGrid.DataSource = CreateDataSource()
ItemsGrid.DataBind()
End Sub
Sub Grid_Change(sender As Object, e As DataGridPageChangedEventArgs)
' For the DataGrid control to navigate to the correct page when paging is
' allowed, the CurrentPageIndex property must be programmatically updated.
' This process is usually accomplished in the event-handling method for the
' PageIndexChanged event.
' Set CurrentPageIndex to the page the user clicked.
ItemsGrid.CurrentPageIndex = e.NewPageIndex
' Re-bind the data to refresh the DataGrid control.
ItemsGrid.DataSource = CreateDataSource()
ItemsGrid.DataBind()
End Sub
</script>
<head runat="server">
<title>DataGrid PageIndexChanged Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DataGrid PageIndexChanged Example</h3>
Select whether to allow paging in the DataGrid control.
<br /><br />
<b>Product List</b>
<asp:DataGrid id="ItemsGrid"
BorderColor="black"
BorderWidth="1"
CellPadding="3"
AutoGenerateColumns="False"
PageSize="10"
AllowPaging="True"
runat="server">
<HeaderStyle BackColor="#00aaaa">
</HeaderStyle>
<Columns>
<asp:BoundColumn DataField="IntegerValue"
SortExpression="IntegerValue"
HeaderText="Item"/>
<asp:BoundColumn DataField="StringValue"
SortExpression="StringValue"
HeaderText="Description"/>
<asp:BoundColumn DataField="CurrencyValue"
HeaderText="Price"
SortExpression="CurrencyValue"
DataFormatString="{0:c}">
<ItemStyle HorizontalAlign="Right">
</ItemStyle>
</asp:BoundColumn>
</Columns>
</asp:DataGrid>
<hr />
<table cellpadding="5">
<tr>
<td>
<asp:CheckBox id="AllowPagingCheckBox"
Text="Allow paging"
AutoPostBack="True"
Checked="True"
OnCheckedChanged="Check_Change"
runat="server"/>
</td>
</tr>
</table>
</form>
</body>
</html>
Poznámky
Událost PageIndexChanged je vyvolána po kliknutí na tlačítko v prvku DataGrid výběru stránky ovládacího prvku.
Při vytváření delegáta DataGridPageChangedEventHandler identifikujete metodu, která bude událost zpracovávat. Pokud chcete událost přidružit k obslužné rutině události, přidejte do události instanci delegáta. Obslužná rutina události je volána při každém výskytu události, dokud neodeberete delegáta. Další informace o delegátech obslužné rutiny událostí najdete v tématu Zpracování a vyvolávání událostí.
Metody rozšíření
| GetMethodInfo(Delegate) |
Získá objekt, který představuje metodu reprezentovanou zadaným delegátem. |
Platí pro
Viz také
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