DataList.ItemTemplate Property
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Gets or sets the template for the items in the DataList control.
public:
virtual property System::Web::UI::ITemplate ^ ItemTemplate { System::Web::UI::ITemplate ^ get(); void set(System::Web::UI::ITemplate ^ value); };
[System.ComponentModel.Browsable(false)]
[System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerProperty)]
[System.Web.UI.TemplateContainer(typeof(System.Web.UI.WebControls.DataListItem))]
public virtual System.Web.UI.ITemplate ItemTemplate { get; set; }
[<System.ComponentModel.Browsable(false)>]
[<System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerProperty)>]
[<System.Web.UI.TemplateContainer(typeof(System.Web.UI.WebControls.DataListItem))>]
member this.ItemTemplate : System.Web.UI.ITemplate with get, set
Public Overridable Property ItemTemplate As ITemplate
Property Value
A ITemplate that contains the template for the items in the DataList control. The default value is null
.
- Attributes
Examples
The following code example demonstrates how to use the ItemTemplate property to control the contents of the items in the DataList control.
Note
The following code sample uses the single-file code model and may not work correctly if copied directly into a code-behind file. This code sample must be copied into an empty text file that has an .aspx extension. For more information on the Web Forms code model, see ASP.NET Web Forms Page Code Model.
<%@ 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 DataList 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)));
dt.Columns.Add(new DataColumn("ImageValue", typeof(String)));
// Populate the table with sample values.
for (int i = 0; i < 9; i++)
{
dr = dt.NewRow();
dr[0] = i;
dr[1] = "Description for item " + i.ToString();
dr[2] = 1.23 * (i + 1);
dr[3] = "Image" + i.ToString() + ".jpg";
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)
{
ItemsList.DataSource = CreateDataSource();
ItemsList.DataBind();
}
}
void Button_Click(Object sender, EventArgs e)
{
// Set the repeat direction based on the selected value of the
// DirectionList DropDownList control.
ItemsList.RepeatDirection =
(RepeatDirection)DirectionList.SelectedIndex;
// Set the repeat layout based on the selected value of the
// LayoutList DropDownList control.
ItemsList.RepeatLayout = (RepeatLayout)LayoutList.SelectedIndex;
// Set the number of columns to display based on the selected
// value of the ColumnsList DropDownList control.
ItemsList.RepeatColumns = ColumnsList.SelectedIndex;
// Show or hide the gridlines based on the value of the
// ShowBorderCheckBox property. Note that gridlines are displayed
// only if the RepeatLayout property is set to Table.
if ((ShowBorderCheckBox.Checked)
&& (ItemsList.RepeatLayout == RepeatLayout.Table))
{
ItemsList.BorderWidth = Unit.Pixel(1);
ItemsList.GridLines = GridLines.Both;
}
else
{
ItemsList.BorderWidth = Unit.Pixel(0);
ItemsList.GridLines = GridLines.None;
}
}
</script>
<head runat="server">
<title>DataList Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DataList Example</h3>
<asp:DataList id="ItemsList"
BorderColor="black"
CellPadding="5"
CellSpacing="5"
RepeatDirection="Vertical"
RepeatLayout="Table"
RepeatColumns="0"
BorderWidth="0"
runat="server">
<HeaderStyle BackColor="#aaaadd">
</HeaderStyle>
<AlternatingItemStyle BackColor="Gainsboro">
</AlternatingItemStyle>
<HeaderTemplate>
List of items
</HeaderTemplate>
<ItemTemplate>
Description: <br />
<%# DataBinder.Eval(Container.DataItem, "StringValue") %>
<br />
Price: <%# DataBinder.Eval(Container.DataItem, "CurrencyValue", "{0:c}") %>
<br />
<asp:Image id="ProductImage"
AlternatingText='<%# DataBinder.Eval(Container.DataItem, "StringValue") %>'
ImageUrl='<%# DataBinder.Eval(Container.DataItem, "ImageValue") %>'
runat="server"/>
</ItemTemplate>
</asp:DataList>
<hr />
<table cellpadding="5">
<tr>
<th>
Repeat direction:
</th>
<th>
Repeat layout:
</th>
<th>
Repeat columns:
</th>
<th>
<asp:CheckBox id="ShowBorderCheckBox"
Text="Show border"
Checked="False"
runat="server" />
</th>
</tr>
<tr>
<td>
<asp:DropDownList id="DirectionList"
runat="server">
<asp:ListItem>Horizontal</asp:ListItem>
<asp:ListItem Selected="True">Vertical</asp:ListItem>
</asp:DropDownList>
</td>
<td>
<asp:DropDownList id="LayoutList"
runat="server">
<asp:ListItem Selected="True">Table</asp:ListItem>
<asp:ListItem>Flow</asp:ListItem>
</asp:DropDownList>
</td>
<td>
<asp:DropDownList id="ColumnsList"
runat="server">
<asp:ListItem Selected="True">0</asp:ListItem>
<asp:ListItem>1</asp:ListItem>
<asp:ListItem>2</asp:ListItem>
<asp:ListItem>3</asp:ListItem>
<asp:ListItem>4</asp:ListItem>
<asp:ListItem>5</asp:ListItem>
</asp:DropDownList>
</td>
<td>
</td>
</tr>
</table>
<asp:LinkButton id="RefreshButton"
Text="Refresh DataList"
OnClick="Button_Click"
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 DataList 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)))
dt.Columns.Add(New DataColumn("ImageValue", GetType(String)))
' Populate the table with sample values.
Dim i As Integer
For i = 0 To 8
dr = dt.NewRow()
dr(0) = i
dr(1) = "Description for item " & i.ToString()
dr(2) = 1.23 * (i + 1)
dr(3) = "Image" & i.ToString() & ".jpg"
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
ItemsList.DataSource = CreateDataSource()
ItemsList.DataBind()
End If
End Sub
Sub Button_Click(sender As Object, e As EventArgs)
' Set the repeat direction based on the selected value of the
' DirectionList DropDownList control.
ItemsList.RepeatDirection = _
CType(DirectionList.SelectedIndex, RepeatDirection)
' Set the repeat layout based on the selected value of the
' LayoutList DropDownList control.
ItemsList.RepeatLayout = CType(LayoutList.SelectedIndex, RepeatLayout)
' Set the number of columns to display based on the selected
' value of the ColumnsList DropDownList control.
ItemsList.RepeatColumns = ColumnsList.SelectedIndex
' Show or hide the gridlines based on the value of the
' ShowBorderCheckBox. Note that gridlines are displayed
' only if the RepeatLayout property is set to Table.
If ShowBorderCheckBox.Checked _
And ItemsList.RepeatLayout = RepeatLayout.Table Then
ItemsList.BorderWidth = Unit.Pixel(1)
ItemsList.GridLines = GridLines.Both
Else
ItemsList.BorderWidth = Unit.Pixel(0)
ItemsList.GridLines = GridLines.None
End If
End Sub
</script>
<head runat="server">
<title>DataList Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DataList Example</h3>
<asp:DataList id="ItemsList"
BorderColor="black"
CellPadding="5"
CellSpacing="5"
RepeatDirection="Vertical"
RepeatLayout="Table"
RepeatColumns="0"
BorderWidth="0"
runat="server">
<HeaderStyle BackColor="#aaaadd">
</HeaderStyle>
<AlternatingItemStyle BackColor="Gainsboro">
</AlternatingItemStyle>
<HeaderTemplate>
List of items
</HeaderTemplate>
<ItemTemplate>
Description: <br />
<%# DataBinder.Eval(Container.DataItem, "StringValue") %>
<br />
Price: <%# DataBinder.Eval(Container.DataItem, "CurrencyValue", "{0:c}") %>
<br />
<asp:Image id="ProductImage"
AlternatingText='<%# DataBinder.Eval(Container.DataItem, "StringValue") %>'
ImageUrl='<%# DataBinder.Eval(Container.DataItem, "ImageValue") %>'
runat="server"/>
</ItemTemplate>
</asp:DataList>
<hr />
<table cellpadding="5">
<tr>
<th>
Repeat direction:
</th>
<th>
Repeat layout:
</th>
<th>
Repeat columns:
</th>
<th>
<asp:CheckBox id="ShowBorderCheckBox"
Text="Show border"
Checked="False"
runat="server" />
</th>
</tr>
<tr>
<td>
<asp:DropDownList id="DirectionList"
runat="server">
<asp:ListItem>Horizontal</asp:ListItem>
<asp:ListItem Selected="True">Vertical</asp:ListItem>
</asp:DropDownList>
</td>
<td>
<asp:DropDownList id="LayoutList"
runat="server">
<asp:ListItem Selected="True">Table</asp:ListItem>
<asp:ListItem>Flow</asp:ListItem>
</asp:DropDownList>
</td>
<td>
<asp:DropDownList id="ColumnsList"
runat="server">
<asp:ListItem Selected="True">0</asp:ListItem>
<asp:ListItem>1</asp:ListItem>
<asp:ListItem>2</asp:ListItem>
<asp:ListItem>3</asp:ListItem>
<asp:ListItem>4</asp:ListItem>
<asp:ListItem>5</asp:ListItem>
</asp:DropDownList>
</td>
<td>
</td>
</tr>
</table>
<asp:LinkButton id="RefreshButton"
Text="Refresh DataList"
OnClick="Button_Click"
runat="server"/>
</form>
</body>
</html>
Remarks
Use the ItemTemplate property to control the contents of the items in the DataList control. The appearance of the items in the DataList control is controlled by the ItemStyle property.
To specify a template for the items of the DataList control, place the <ItemTemplate>
tags between the opening and closing tags of the DataList control. You can then list the contents of the template between the opening and closing <ItemTemplate>
tags.
You can optionally use the AlternatingItemTemplate property to provide a different appearance for the alternating items in the DataList control.
Caution
This control can be used to display user input, which might include malicious client script. Check any information that is sent from a client for executable script, SQL statements, or other code before displaying it in your application. You can use validation controls to verify user input before displaying the input text in a control. ASP.NET provides an input request validation feature to block script and HTML in user input. For more information, see Securing Standard Controls, How to: Protect Against Script Exploits in a Web Application by Applying HTML Encoding to Strings, and Validating User Input in ASP.NET Web Pages.