DataGrid.SelectedIndex Eigenschaft
Definition
Wichtig
Einige Informationen beziehen sich auf Vorabversionen, die vor dem Release ggf. grundlegend überarbeitet werden. Microsoft übernimmt hinsichtlich der hier bereitgestellten Informationen keine Gewährleistungen, seien sie ausdrücklich oder konkludent.
Ruft den Index des ausgewählten Elements im DataGrid-Steuerelement ab oder legt diesen fest.
public:
virtual property int SelectedIndex { int get(); void set(int value); };[System.ComponentModel.Bindable(true)]
public virtual int SelectedIndex { get; set; }[<System.ComponentModel.Bindable(true)>]
member this.SelectedIndex : int with get, setPublic Overridable Property SelectedIndex As IntegerEigenschaftswert
Der Index des ausgewählten Elements im DataGrid-Steuerelement.
- Attribute
Ausnahmen
Der angegebene Index ist kleiner als -1.
Beispiele
Im folgenden Codebeispiel wird veranschaulicht, wie die SelectedIndex Eigenschaft verwendet wird, um die Indexnummer des ausgewählten Elements im DataGrid Steuerelement zu bestimmen. Außerdem wird gezeigt, wie Sie ein Element programmgesteuert auswählen und deaktivieren.
<%@ 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 language="C#" runat="server">
DataTable Cart = new DataTable();
DataView CartView;
void Page_Load(Object sender, EventArgs e)
{
DataRow dr;
if (Session["ShoppingCart"] == null)
{
Cart.Columns.Add(new DataColumn("Qty", typeof(String)));
Cart.Columns.Add(new DataColumn("Item", typeof(String)));
Cart.Columns.Add(new DataColumn("Price", typeof(String)));
Session["ShoppingCart"] = Cart;
// Create rows and add sample data.
for (int i = 1; i <= 9; i++)
{
dr = Cart.NewRow();
if (i % 2 != 0)
dr[0] = "2";
else
dr[0] = "1";
dr[1] = "Item " + i.ToString();
dr[2] = (1.23 * (i + 1)).ToString();
Cart.Rows.Add(dr);
}
}
else
Cart = (DataTable)Session["ShoppingCart"];
CartView = new DataView(Cart);
CartView.Sort="Item";
if (!IsPostBack)
BindGrid();
}
void MyDataGrid_Select(Object sender, EventArgs e)
{
Label1.Text = "You selected " +
MyDataGrid.SelectedItem.Cells[1].Text +
".<br />" +
MyDataGrid.SelectedItem.Cells[1].Text +
" has an index number of " +
MyDataGrid.SelectedIndex.ToString() + ".";
}
void Select_Button_Click(Object sender, EventArgs e)
{
MyDataGrid.SelectedIndex = 4;
}
void UnSelect_Button_Click(Object sender, EventArgs e)
{
MyDataGrid.SelectedIndex = -1;
Label1.Text = "";
}
void BindGrid()
{
MyDataGrid.DataSource = CartView;
MyDataGrid.DataBind();
}
</script>
<head runat="server">
<title>DataGrid Selection Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DataGrid Selection Example</h3>
<asp:DataGrid id="MyDataGrid" runat="server"
BorderColor="black"
BorderWidth="1"
CellPadding="3"
Font-Names="Verdana"
Font-Size="8pt"
OnSelectedIndexChanged="MyDataGrid_Select"
AutoGenerateColumns="false">
<HeaderStyle BackColor="#aaaadd">
</HeaderStyle>
<SelectedItemStyle BackColor="Yellow">
</SelectedItemStyle>
<Columns>
<asp:ButtonColumn
HeaderText="Select Item"
ButtonType="LinkButton"
Text="Select"
CommandName="Select">
</asp:ButtonColumn>
<asp:BoundColumn
HeaderText="Item"
ReadOnly="true"
DataField="Item"/>
<asp:BoundColumn
HeaderText="Quantity"
DataField="Qty"/>
<asp:BoundColumn
HeaderText="Price"
DataField="Price"/>
</Columns>
</asp:DataGrid>
<br /><br />
<asp:Button id="Button1"
Text="Select Item 5"
OnClick="Select_Button_Click"
runat="server"/>
<asp:Button id="Button2"
Text="Unselect Item"
OnClick="UnSelect_Button_Click"
runat="server"/>
<br /><br />
<asp:Label id="Label1" runat="server"/>
</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 language="VB" runat="server">
Dim Cart As New DataTable
Dim CartView As DataView
Sub Page_Load(sender As Object, e As EventArgs)
Dim dr As DataRow
If Session("ShoppingCart") Is Nothing Then
Cart.Columns.Add(New DataColumn("Qty", GetType(String)))
Cart.Columns.Add(New DataColumn("Item", GetType(String)))
Cart.Columns.Add(New DataColumn("Price", GetType(String)))
Session("ShoppingCart") = Cart
' Create rows and add sample data.
Dim i As Integer
For i = 1 To 9
dr = Cart.NewRow()
If i Mod 2 <> 0 Then
dr(0) = "2"
Else
dr(0) = "1"
End If
dr(1) = "Item " & i.ToString()
dr(2) =(1.23 *(i + 1)).ToString()
Cart.Rows.Add(dr)
Next i
Else
Cart = CType(Session("ShoppingCart"), DataTable)
End If
CartView = New DataView(Cart)
CartView.Sort = "Item"
If Not IsPostBack Then
BindGrid()
End If
End Sub 'Page_Load
Sub MyDataGrid_Select(sender As Object, e As EventArgs)
Label1.Text = "You selected " & MyDataGrid.SelectedItem.Cells(1).Text & _
".<br />" & MyDataGrid.SelectedItem.Cells(1).Text & " has an index number of " & _
MyDataGrid.SelectedIndex.ToString() & "."
End Sub 'MyDataGrid_Select
Sub Select_Button_Click(sender As Object, e As EventArgs)
MyDataGrid.SelectedIndex = 4
End Sub 'Select_Button_Click
Sub UnSelect_Button_Click(sender As Object, e As EventArgs)
MyDataGrid.SelectedIndex = - 1
Label1.Text = ""
End Sub 'UnSelect_Button_Click
Sub BindGrid()
MyDataGrid.DataSource = CartView
MyDataGrid.DataBind()
End Sub 'BindGrid
</script>
<head runat="server">
<title>DataGrid Selection Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DataGrid Selection Example</h3>
<asp:DataGrid id="MyDataGrid" runat="server"
BorderColor="black"
BorderWidth="1"
CellPadding="3"
Font-Names="Verdana"
Font-Size="8pt"
OnSelectedIndexChanged="MyDataGrid_Select"
AutoGenerateColumns="false">
<HeaderStyle BackColor="#aaaadd">
</HeaderStyle>
<SelectedItemStyle BackColor="Yellow">
</SelectedItemStyle>
<Columns>
<asp:ButtonColumn
HeaderText="Select Item"
ButtonType="LinkButton"
Text="Select"
CommandName="Select">
</asp:ButtonColumn>
<asp:BoundColumn
HeaderText="Item"
ReadOnly="true"
DataField="Item"/>
<asp:BoundColumn
HeaderText="Quantity"
DataField="Qty"/>
<asp:BoundColumn
HeaderText="Price"
DataField="Price"/>
</Columns>
</asp:DataGrid>
<br /><br />
<asp:Button id="Button1"
Text="Select Item 5"
OnClick="Select_Button_Click"
runat="server"/>
<asp:Button id="Button2"
Text="Unselect Item"
OnClick="UnSelect_Button_Click"
runat="server"/>
<br /><br />
<asp:Label id="Label1" runat="server"/>
</form>
</body>
</html>
Hinweise
Verwenden Sie die SelectedIndex Eigenschaft, um den Index des elements zu bestimmen, das vom Benutzer im DataGrid Steuerelement ausgewählt wurde. Sie können diese Eigenschaft auch verwenden, um programmgesteuert anzugeben, welches Element im DataGrid Steuerelement ausgewählt ist.
Um ein Element im DataGrid Steuerelement zu deaktivieren, legen Sie diese Eigenschaft auf -1 fest.