DataGrid.Items 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 eine Auflistung der DataGridItem-Objekte ab, die die einzelnen Elemente im DataGrid-Steuerelement darstellen.
public:
virtual property System::Web::UI::WebControls::DataGridItemCollection ^ Items { System::Web::UI::WebControls::DataGridItemCollection ^ get(); };
[System.ComponentModel.Browsable(false)]
public virtual System.Web.UI.WebControls.DataGridItemCollection Items { get; }
[<System.ComponentModel.Browsable(false)>]
member this.Items : System.Web.UI.WebControls.DataGridItemCollection
Public Overridable ReadOnly Property Items As DataGridItemCollection
Eigenschaftswert
Eine DataGridItemCollection, die eine Auflistung der DataGridItem-Objekte enthält, die die einzelnen Elemente im DataGrid-Steuerelement darstellen.
- Attribute
Beispiele
Im folgenden Codebeispiel wird veranschaulicht, wie die Items Auflistung verwendet wird, um den Inhalt der einzelnen Elemente im DataGrid Steuerelement anzuzeigen.
<%@ 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;
DataView CartView;
ICollection CreateDataSource()
{
DataTable dt = new DataTable();
DataRow dr;
dt.Columns.Add(new DataColumn("IntegerValue", typeof(Int32)));
dt.Columns.Add(new DataColumn("StringValue", typeof(string)));
dt.Columns.Add(new DataColumn("CurrencyValue", typeof(double)));
for (int i = 0; i < 10; 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)
{
if (!IsPostBack)
{
// Need to load this data only once.
ItemsGrid.DataSource = CreateDataSource();
ItemsGrid.DataBind();
}
}
void Button_Click(Object sender, EventArgs e)
{
foreach (DataGridItem item in ItemsGrid.Items)
{
Label1.Text += "<br />" + item.Cells[0].Text +
" " + item.Cells[1].Text +
" " + item.Cells[2].Text;
}
}
</script>
<head runat="server">
<title>DataGrid Items Collection Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DataGrid Items Collection Example</h3>
<asp:DataGrid id="ItemsGrid" runat="server"
BorderColor="black"
BorderWidth="1"
CellPadding="3"
ShowFooter="true"
AutoGenerateColumns="true">
<HeaderStyle BackColor="#00aaaa">
</HeaderStyle>
<FooterStyle BackColor="#00aaaa">
</FooterStyle>
</asp:DataGrid>
<br />
<asp:Button id="Button1"
Text="Display Contents of Items Collection"
OnClick="Button_Click"
runat="server"/>
<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 DataTable
Dim CartView As DataView
Function CreateDataSource() As ICollection
Dim dt As New DataTable()
Dim dr As DataRow
dt.Columns.Add(New DataColumn("IntegerValue", GetType(Int32)))
dt.Columns.Add(New DataColumn("StringValue", GetType(String)))
dt.Columns.Add(New DataColumn("CurrencyValue", GetType(Double)))
Dim i As Integer
For i = 0 To 9
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 New DataView(dt)
Return dv
End Function 'CreateDataSource
Sub Page_Load(sender As Object, e As EventArgs)
If Not IsPostBack Then
' Need to load this data only once.
ItemsGrid.DataSource = CreateDataSource()
ItemsGrid.DataBind()
End If
End Sub 'Page_Load
Sub Button_Click(sender As Object, e As EventArgs)
Dim item As DataGridItem
For Each item In ItemsGrid.Items
Label1.Text &= "<br />" & item.Cells(0).Text & _
" " & item.Cells(1).Text & _
" " & item.Cells(2).Text
Next item
End Sub 'Button_Click
</script>
<head runat="server">
<title>DataGrid Items Collection Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DataGrid Items Collection Example</h3>
<asp:DataGrid id="ItemsGrid" runat="server"
BorderColor="black"
BorderWidth="1"
CellPadding="3"
ShowFooter="true"
AutoGenerateColumns="true">
<HeaderStyle BackColor="#00aaaa">
</HeaderStyle>
<FooterStyle BackColor="#00aaaa">
</FooterStyle>
</asp:DataGrid>
<br />
<asp:Button id="Button1"
Text="Display Contents of Items Collection"
OnClick="Button_Click"
runat="server"/>
<br />
<asp:Label id="Label1"
runat="server"/>
</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 < 5; 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();
}
}
void Button_Click(Object sender, EventArgs e)
{
// Count the number of selected items in the DataGrid control.
int count = 0;
// Display the selected times.
Message.Text = "You Selected: <br />";
// Iterate through each item (row) in the DataGrid control and
// determine whether it is selected.
foreach (DataGridItem item in ItemsGrid.Items)
{
DetermineSelection(item, ref count);
}
// If no items are selected, display the appropriate message.
if (count == 0)
{
Message.Text = "No items selected";
}
}
void DetermineSelection(DataGridItem item, ref int count)
{
// Retrieve the SelectCheckBox CheckBox control from the
// specified item (row) in the DataGrid control.
CheckBox selection = (CheckBox)item.FindControl("SelectCheckBox");
// If the item is selected, display the appropriate message and
// increment the count of selected items.
if (selection != null)
{
if (selection.Checked)
{
Message.Text += "- " + item.Cells[1].Text + "<br />";
count++;
}
}
}
void Check_Change(Object sender, EventArgs e)
{
// Show or hide the first column depending on the value of
// the check box.
if (ShowCheckBox.Checked)
{
ItemsGrid.Columns[0].Visible = true;
}
else
{
ItemsGrid.Columns[0].Visible = false;
}
}
</script>
<head runat="server">
<title>DataGridColumn Visible Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DataGridColumn Visible Example</h3>
Select whether to show or hide the first column.
<br /><br />
<b>Product List</b>
<asp:DataGrid id="ItemsGrid"
BorderColor="black"
BorderWidth="1"
CellPadding="3"
ShowFooter="True"
AutoGenerateColumns="False"
runat="server">
<HeaderStyle BackColor="#00aaaa">
</HeaderStyle>
<FooterStyle BackColor="#00aaaa">
</FooterStyle>
<Columns>
<asp:BoundColumn DataField="IntegerValue"
Visible="True"
HeaderText="Item"/>
<asp:BoundColumn DataField="StringValue"
Visible="True"
HeaderText="Description"/>
<asp:BoundColumn DataField="CurrencyValue"
Visible="True"
HeaderText="Price"
DataFormatString="{0:c}">
<ItemStyle HorizontalAlign="Right">
</ItemStyle>
</asp:BoundColumn>
<asp:TemplateColumn HeaderText="Select Item"
Visible="True" >
<ItemTemplate>
<asp:CheckBox id="SelectCheckBox"
Text="Add to Cart"
Checked="False"
runat="server"/>
</ItemTemplate>
</asp:TemplateColumn>
</Columns>
</asp:DataGrid>
<br /><br />
<asp:Button id="SubmitButton"
Text="Submit"
OnClick = "Button_Click"
runat="server"/>
<br /><br />
<asp:Label id="Message"
runat="server"/>
<hr />
<asp:CheckBox id="ShowCheckBox"
Text="Show first column"
AutoPostBack="True"
OnCheckedChanged="Check_Change"
Checked="True"
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 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 4
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
End Sub
Sub Button_Click(sender As Object, e As EventArgs)
' Count the number of selected items in the DataGrid control.
Dim count As Integer = 0
' Display the selected times.
Message.Text = "You Selected: <br />"
' Iterate through each item (row) in the DataGrid control and
' determine whether it is selected.
Dim item As DataGridItem
For Each item In ItemsGrid.Items
DetermineSelection(item, count)
Next
' If no items are selected, display the appropriate message.
If count = 0 Then
Message.Text = "No items selected"
End If
End Sub
Sub DetermineSelection(item As DataGridItem, ByRef count As Integer)
' Retrieve the SelectCheckBox CheckBox control from the
' specified item (row) in the DataGrid control.
Dim selection As CheckBox = _
CType(item.FindControl("SelectCheckBox"), CheckBox)
' If the item is selected, display the appropriate message and
' increment the count of selected items.
If Not selection Is Nothing Then
If selection.Checked Then
Message.Text &= "- " & item.Cells(1).Text & "<br />"
count = count + 1
End If
End If
End Sub
Sub Check_Change(sender As Object, e As EventArgs)
' Show or hide the first column depending on the value of
' the check box.
If ShowCheckBox.Checked Then
ItemsGrid.Columns(0).Visible = True
Else
ItemsGrid.Columns(0).Visible = False
End If
End Sub
</script>
<head runat="server">
<title>DataGridColumn Visible Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DataGridColumn Visible Example</h3>
Select whether to show or hide the first column.
<br /><br />
<b>Product List</b>
<asp:DataGrid id="ItemsGrid"
BorderColor="black"
BorderWidth="1"
CellPadding="3"
ShowFooter="True"
AutoGenerateColumns="False"
runat="server">
<HeaderStyle BackColor="#00aaaa">
</HeaderStyle>
<FooterStyle BackColor="#00aaaa">
</FooterStyle>
<Columns>
<asp:BoundColumn DataField="IntegerValue"
Visible="True"
HeaderText="Item"/>
<asp:BoundColumn DataField="StringValue"
Visible="True"
HeaderText="Description"/>
<asp:BoundColumn DataField="CurrencyValue"
Visible="True"
HeaderText="Price"
DataFormatString="{0:c}">
<ItemStyle HorizontalAlign="Right">
</ItemStyle>
</asp:BoundColumn>
<asp:TemplateColumn HeaderText="Select Item"
Visible="True" >
<ItemTemplate>
<asp:CheckBox id="SelectCheckBox"
Text="Add to Cart"
Checked="False"
runat="server"/>
</ItemTemplate>
</asp:TemplateColumn>
</Columns>
</asp:DataGrid>
<br /><br />
<asp:Button id="SubmitButton"
Text="Submit"
OnClick = "Button_Click"
runat="server"/>
<br /><br />
<asp:Label id="Message"
runat="server"/>
<hr />
<asp:CheckBox id="ShowCheckBox"
Text="Show first column"
AutoPostBack="True"
OnCheckedChanged="Check_Change"
Checked="True"
runat="server"/>
</form>
</body>
</html>
Hinweise
Verwenden Sie die Items Auflistung, um die Elemente im DataGrid Steuerelement programmgesteuert zu steuern. Die Items Auflistung stellt keine Methoden zum Hinzufügen oder Entfernen von Elementen zur Auflistung bereit. Sie können jedoch den Inhalt eines Elements steuern, indem Sie einen Handler für das ItemCreated Ereignis bereitstellen.
Hinweis
Nur elemente, die an die Datenquelle gebunden sind, sind in der Items Auflistung enthalten. Kopfzeile, Fußzeile und Trennzeichen sind nicht in der Auflistung enthalten.