DataGrid.SelectedItemStyle Proprietà
Definizione
Importante
Alcune informazioni sono relative alla release non definitiva del prodotto, che potrebbe subire modifiche significative prima della release definitiva. Microsoft non riconosce alcuna garanzia, espressa o implicita, in merito alle informazioni qui fornite.
Ottiene le proprietà di stile dell'elemento attualmente selezionato nel controllo DataGrid.
public:
virtual property System::Web::UI::WebControls::TableItemStyle ^ SelectedItemStyle { System::Web::UI::WebControls::TableItemStyle ^ get(); };[System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerProperty)]
public virtual System.Web.UI.WebControls.TableItemStyle SelectedItemStyle { get; }[<System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerProperty)>]
member this.SelectedItemStyle : System.Web.UI.WebControls.TableItemStylePublic Overridable ReadOnly Property SelectedItemStyle As TableItemStyleValore della proprietà
Un oggetto TableItemStyle che contiene le proprietà di stile dell'elemento attualmente selezionato nel controllo DataGrid. Il valore predefinito è un oggetto TableItemStyle vuoto.
- Attributi
Esempio
Nell'esempio di codice seguente viene illustrato come usare SelectedItemStyle la proprietà per impostare il colore di sfondo dell'elemento selezionato nel DataGrid controllo su giallo.
<%@ 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>
<%@ 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>
<title>DataGrid SelectedItemStyle 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 />";
}
void Selection_Change(Object sender, EventArgs e)
{
// Set the background color for the paging controls section of
// the DataGrid control.
ItemsGrid.SelectedItemStyle.BackColor = System.Drawing.Color.FromName(List.SelectedItem.Value);
}
</script>
</head>
<body>
<form id="form1" runat="server">
<h3>DataGrid SelectedItemStyle Example</h3>
Select an item and a backcolor for the selected item.
<br /><br />
<asp:DataGrid id="ItemsGrid"
BorderColor="Black"
ShowFooter="False"
CellPadding="3"
CellSpacing="0"
HeaderStyle-BackColor="#aaaadd"
OnSelectedIndexChanged="IndexChange_Command"
runat="server">
<SelectedItemStyle BackColor="White">
</SelectedItemStyle>
<Columns>
<asp:ButtonColumn Text="Select"
CommandName="Select"/>
</Columns>
</asp:DataGrid>
<hr />
<table style="border-color:Black; border-width:1" cellspacing="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>
<table cellpadding="5">
<tr>
<td>
Backcolor:
</td>
</tr>
<tr>
<td>
<asp:DropDownList id="List"
AutoPostBack="True"
OnSelectedIndexChanged="Selection_Change"
runat="server">
<asp:ListItem Selected="True" Value="White"> White </asp:ListItem>
<asp:ListItem Value="Silver"> Silver </asp:ListItem>
<asp:ListItem Value="DarkGray"> Dark Gray </asp:ListItem>
<asp:ListItem Value="Khaki"> Khaki </asp:ListItem>
<asp:ListItem Value="DarkKhaki"> Dark Khaki </asp:ListItem>
</asp:DropDownList>
</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>
<title>DataGrid SelectedItemStyle 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
Sub Selection_Change(sender As Object, e As EventArgs)
' Set the background color for the paging controls section of
' the DataGrid control.
ItemsGrid.SelectedItemStyle.BackColor = System.Drawing.Color.FromName(List.SelectedItem.Value)
End Sub
</script>
</head>
<body>
<form id="form1" runat="server">
<h3>DataGrid SelectedItemStyle Example</h3>
Select an item and a backcolor for the selected item.
<br /><br />
<asp:DataGrid id="ItemsGrid"
BorderColor="Black"
ShowFooter="False"
CellPadding="3"
CellSpacing="0"
HeaderStyle-BackColor="#aaaadd"
OnSelectedIndexChanged="IndexChange_Command"
runat="server">
<SelectedItemStyle BackColor="White">
</SelectedItemStyle>
<Columns>
<asp:ButtonColumn Text="Select"
CommandName="Select"/>
</Columns>
</asp:DataGrid>
<hr />
<table style="border-color:Black; border-width:1" cellspacing="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>
<table cellpadding="5">
<tr>
<td>
Backcolor:
</td>
</tr>
<tr>
<td>
<asp:DropDownList id="List"
AutoPostBack="True"
OnSelectedIndexChanged="Selection_Change"
runat="server">
<asp:ListItem Selected="True" Value="White"> White </asp:ListItem>
<asp:ListItem Value="Silver"> Silver </asp:ListItem>
<asp:ListItem Value="DarkGray"> Dark Gray </asp:ListItem>
<asp:ListItem Value="Khaki"> Khaki </asp:ListItem>
<asp:ListItem Value="DarkKhaki"> Dark Khaki </asp:ListItem>
</asp:DropDownList>
</td>
</tr>
</table>
</form>
</body>
</html>
Commenti
Utilizzare la SelectedItemStyle proprietà per specificare uno stile personalizzato per l'elemento selezionato nel DataGrid controllo. Gli attributi di stile comuni che possono essere modificati includono forecolor, backcolor, font e allineamento del contenuto all'interno della cella. Fornendo uno stile diverso migliora l'aspetto del DataGrid controllo.
Le proprietà dello stile di elemento nel DataGrid controllo vengono ereditate da una proprietà dello stile di elemento a un'altra tramite una gerarchia. Le proprietà dello stile di elemento impostate più in basso nella gerarchia vengono ereditate dalle proprietà dello stile di elemento superiori nella gerarchia. Ad esempio, se si specifica un carattere rosso per la ItemStyle proprietà, tutte le altre proprietà dello stile di elemento nel DataGrid controllo avranno anche un carattere rosso. In questo modo è possibile fornire un aspetto comune per il controllo impostando una singola proprietà di stile elemento. È possibile eseguire l'override delle impostazioni di stile ereditate per una proprietà di stile dell'elemento superiore nella gerarchia impostandone le proprietà di stile. Ad esempio, è possibile specificare un carattere blu per la AlternatingItemStyle proprietà, sostituendo il carattere rosso specificato nella ItemStyle proprietà. La tabella seguente elenca l'ordine della gerarchia dal più alto al più basso.
| Precedenza | Style, proprietà |
|---|---|
| 1 | EditItemStyle |
| 2 | SelectedItemStyle |
| 3 | AlternatingItemStyle |
| 4 | ItemStyle |
| 5 | ControlStyle |
Per specificare uno stile personalizzato per l'elemento selezionato, posizionare i <SelectedItemStyle> tag tra i tag di apertura e chiusura del DataGrid controllo. È quindi possibile elencare gli attributi di stile all'interno del tag di apertura <SelectedItemStyle> .