BaseDataList.SelectedIndexChanged Událost
Definice
Důležité
Některé informace platí pro předběžně vydaný produkt, který se může zásadně změnit, než ho výrobce nebo autor vydá. Microsoft neposkytuje žádné záruky, výslovné ani předpokládané, týkající se zde uváděných informací.
Vyvolá se při výběru jiné položky v ovládacím prvku výpisu dat mezi příspěvky na server.
public:
event EventHandler ^ SelectedIndexChanged;public event EventHandler SelectedIndexChanged;member this.SelectedIndexChanged : EventHandler Public Custom Event SelectedIndexChanged As EventHandler Event Type
Příklady
Následující příklad kódu ukazuje, jak poskytnout obslužnou rutinu SelectedIndexChanged události deklarativně.
<%@ Page Language="C#" AutoEventWireup="True"%>
<%@ Import Namespace="System.Data" %>
<%@ Import Namespace="System.Data.SqlClient" %>
<!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" >
<head runat="server">
<title>Declarative BaseDataList SelectedIndexChanged Example</title>
<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 < 9; i++)
{
dr = dt.NewRow();
dr[0] = i;
dr[1] = "Item " + i.ToString();
dr[2] = 1.23 * (i + 1);
dt.Rows.Add(dr);
}
// Create a DataView from the DataTable.
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();
}
}
void IndexChange_Command(Object sender, EventArgs e)
{
// Display the details of the selected item.
DetailsLabel.Text =
"Item Number: " + ItemsGrid.SelectedItem.Cells[1].Text + "<br />" +
"Description: " + ItemsGrid.SelectedItem.Cells[2].Text + "<br />" +
"Price: $" + ItemsGrid.SelectedItem.Cells[3].Text + "<br />";
}
</script>
</head>
<body>
<form id="form1" runat="server">
<h3>Declarative BaseDataList SelectedIndexChanged Example</h3>
Select an item:
<br /><br />
<asp:DataGrid id="ItemsGrid"
BorderColor="Black"
ShowFooter="False"
CellPadding="3"
CellSpacing="0"
HeaderStyle-BackColor="#aaaadd"
OnSelectedIndexChanged="IndexChange_Command"
runat="server">
<Columns>
<asp:ButtonColumn Text="Select"
CommandName="Select"/>
</Columns>
</asp:DataGrid>
<hr />
<table style="border-width:1; border-color:Black; margin:0">
<tr style="background-color:#aaaadd">
<td>
Details
</td>
</tr>
<tr>
<td>
<asp:Label id="DetailsLabel"
runat="server"
Text="No item selected."/>
</td>
</tr>
</table>
</form>
</body>
</html>
<%@ Page Language="VB" AutoEventWireup="True"%>
<%@ Import Namespace="System.Data" %>
<%@ Import Namespace="System.Data.SqlClient" %>
<!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" >
<head runat="server">
<title>Declarative BaseDataList SelectedIndexChanged Example</title>
<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(Integer)))
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 8
dr = dt.NewRow()
dr(0) = i
dr(1) = "Item " & i.ToString()
dr(2) = 1.23 * (i + 1)
dt.Rows.Add(dr)
Next i
' Create a DataView from the DataTable.
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
End Sub
Sub IndexChange_Command(sender As Object, e As EventArgs)
' Display the details of the selected item.
DetailsLabel.Text = _
"Item Number: " & ItemsGrid.SelectedItem.Cells(1).Text & "<br />" & _
"Description: " & ItemsGrid.SelectedItem.Cells(2).Text & "<br />" & _
"Price: $" & ItemsGrid.SelectedItem.Cells(3).Text & "<br />"
End Sub
</script>
</head>
<body>
<form id="form1" runat="server">
<h3>Declarative BaseDataList SelectedIndexChanged Example</h3>
Select an item:
<br /><br />
<asp:DataGrid id="ItemsGrid"
BorderColor="Black"
ShowFooter="False"
CellPadding="3"
CellSpacing="0"
HeaderStyle-BackColor="#aaaadd"
OnSelectedIndexChanged="IndexChange_Command"
runat="server">
<Columns>
<asp:ButtonColumn Text="Select"
CommandName="Select"/>
</Columns>
</asp:DataGrid>
<hr />
<table border="1" style="border-color:Black; margin:0">
<tr style="background-color:#aaaadd">
<td>
Details
</td>
</tr>
<tr>
<td>
<asp:Label id="DetailsLabel"
runat="server"
Text="No item selected."/>
</td>
</tr>
</table>
</form>
</body>
</html>
Následující příklad kódu ukazuje, jak poskytnout obslužnou rutinu SelectedIndexChanged události pro událost prostřednictvím kódu programu.
<%@ Page Language="C#" AutoEventWireup="True"%>
<%@ Import Namespace="System.Data" %>
<%@ Import Namespace="System.Data.SqlClient" %>
<!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" >
<head runat="server">
<title>Programmatic BaseDataList SelectedIndexChanged Example</title>
<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 < 9; i++)
{
dr = dt.NewRow();
dr[0] = i;
dr[1] = "Item " + i.ToString();
dr[2] = 1.23 * (i + 1);
dt.Rows.Add(dr);
}
// Create a DataView from the DataTable.
DataView dv = new DataView(dt);
return dv;
}
void IndexChange_Command(Object sender, EventArgs e)
{
// Display the details of the selected item.
DetailsLabel.Text = "Item Number: " + ItemsGrid.SelectedItem.Cells[1].Text + "<br />" +
"Description: " + ItemsGrid.SelectedItem.Cells[2].Text + "<br />" +
"Price: $" + ItemsGrid.SelectedItem.Cells[3].Text + "<br />";
}
void Page_Load(Object sender, EventArgs e)
{
// Load sample data only once, when the page is first loaded.
if (!IsPostBack)
{
// Load sample data.
ItemsGrid.DataSource = CreateDataSource();
ItemsGrid.DataBind();
}
// Register event-handling methods.
ItemsGrid.SelectedIndexChanged += new EventHandler(this.IndexChange_Command);
}
</script>
</head>
<body>
<form id="form1" runat="server">
<h3>Programmatic BaseDataList SelectedIndexChanged Example</h3>
Select an item:
<br /><br />
<asp:DataGrid id="ItemsGrid"
BorderColor="Black"
ShowFooter="False"
CellPadding="3"
CellSpacing="0"
HeaderStyle-BackColor="#aaaadd"
runat="server">
<Columns>
<asp:ButtonColumn Text="Select"
CommandName="Select"/>
</Columns>
</asp:DataGrid>
<hr />
<table border="1" style="border-color:Black; margin:0">
<tr style="background-color:#aaaadd">
<td>
Details
</td>
</tr>
<tr>
<td>
<asp:Label id="DetailsLabel"
runat="server"
Text="No item selected."/>
</td>
</tr>
</table>
</form>
</body>
</html>
<%@ Page Language="VB" AutoEventWireup="True"%>
<%@ Import Namespace="System.Data" %>
<%@ Import Namespace="System.Data.SqlClient" %>
<!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" >
<head runat="server">
<title>Programmatic BaseDataList SelectedIndexChanged Example</title>
<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(Integer)))
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 8
dr = dt.NewRow()
dr(0) = i
dr(1) = "Item " & i.ToString()
dr(2) = 1.23 * (i + 1)
dt.Rows.Add(dr)
Next i
' Create a DataView from the DataTable.
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
' Register event-handling methods.
AddHandler ItemsGrid.SelectedIndexChanged, AddressOf IndexChange_Command
End Sub
Sub IndexChange_Command(sender As Object, e As EventArgs)
' Display the details of the selected item.
DetailsLabel.Text = "Item Number: " & ItemsGrid.SelectedItem.Cells(1).Text & "<br />" & _
"Description: " & ItemsGrid.SelectedItem.Cells(2).Text & "<br />" & _
"Price: $" & ItemsGrid.SelectedItem.Cells(3).Text & "<br />"
End Sub
</script>
</head>
<body>
<form id="form1" runat="server">
<h3>Programmatic BaseDataList SelectedIndexChanged Example</h3>
Select an item:
<br /><br />
<asp:DataGrid id="ItemsGrid"
BorderColor="Black"
ShowFooter="False"
CellPadding="3"
CellSpacing="0"
HeaderStyle-BackColor="#aaaadd"
DataKeyField="IntegerValue"
OnSelectedIndexChanged="IndexChange_Command"
runat="server">
<Columns>
<asp:ButtonColumn Text="Select"
CommandName="Select"/>
</Columns>
</asp:DataGrid>
<hr />
<table border="1" style="border-color:Black; margin:0">
<tr style="background-color:#aaaadd">
<td>
Details
</td>
</tr>
<tr>
<td>
<asp:Label id="DetailsLabel"
runat="server"
Text="No item selected."/>
</td>
</tr>
</table>
</form>
</body>
</html>
Poznámky
Událost SelectedIndexChanged je vyvolána, když je vybrána jiná položka v ovládacím prvku výpisu dat mezi příspěvky na server.
Další informace o zpracování událostí najdete v tématu Zpracování a vyvolávání událostí.
Platí pro
Viz také
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