DataList.ItemCreated 事件
当在 DataList 控件中创建项时在服务器上发生。
**命名空间:**System.Web.UI.WebControls
**程序集:**System.Web（在 system.web.dll 中）
语法
声明
Public Event ItemCreated As DataListItemEventHandler
用法
Dim instance As DataList
Dim handler As DataListItemEventHandler
AddHandler instance.ItemCreated, handler
public event DataListItemEventHandler ItemCreated
public:
event DataListItemEventHandler^ ItemCreated {
void add (DataListItemEventHandler^ value);
void remove (DataListItemEventHandler^ value);
}
/** @event */
public void add_ItemCreated (DataListItemEventHandler value)
/** @event */
public void remove_ItemCreated (DataListItemEventHandler value)
JScript 支持使用事件，但不支持进行新的声明。
备注
当创建 DataList 控件中的项时（不论是在往返行程中还是在将数据绑定到控件时），都会引发 ItemCreated 事件。
ItemCreated 事件通常用于控制 DataList 控件中行的内容和外观。
有关处理事件的更多信息，请参见 如何：在 Web 窗体应用程序中使用事件。
| 主题 | 位置 |
|---|---|
| 如何：在运行时自定义 DataList 项 | 在 Visual Studio 中生成 ASP .NET Web 应用程序 |
| 如何：在运行时自定义 DataList 项 | 在 Visual Studio 中生成 ASP .NET Web 应用程序 |
| 如何：在运行时自定义 DataList 项 | 生成 ASP .NET Web 应用程序 |
示例
下面的代码示例演示如何为 ItemCreated 事件指定和编写处理程序，以显示在 DataList 控件中创建项的顺序。
提示
以下代码示例使用单文件代码模型，当它直接复制到代码隐藏文件时可能不能正常工作。此代码示例必须被复制到具有 .aspx 扩展名的空文本文件中。有关 Web 窗体代码模型的更多信息，请参见 ASP.NET 网页代码模型。
<%@ Page Language="VB" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<html>
<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)))
' 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)
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 Item_Created(sender As Object, e As DataListItemEventArgs)
If e.Item.ItemType = ListItemType.Item Or _
e.Item.ItemType = ListItemType.AlternatingItem Then
' Retrieve the Label control in the current DataListItem.
Dim PriceLabel As Label = _
CType(e.Item.FindControl("PriceLabel"), Label)
' Retrieve the text of the CurrencyColumn from the DataListItem
' and convert the value to a Double.
Dim Price As Double = Convert.ToDouble( _
(CType(e.Item.DataItem, DataRowView)).Row.ItemArray(2).ToString())
' Format the value as currency and redisplay it in the DataList.
PriceLabel.Text = Price.ToString("c")
End If
End Sub
</script>
<body>
<form runat=server>
<h3>DataList ItemCreated Example</h3>
<asp:DataList id="ItemsList"
BorderColor="black"
CellPadding="5"
CellSpacing="5"
RepeatDirection="Vertical"
RepeatLayout="Table"
RepeatColumns="3"
ShowBorder="True"
OnItemCreated="Item_Created"
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:
<asp:Label id="PriceLabel"
runat="server"/>
</ItemTemplate>
</asp:DataList>
</form>
</body>
</html>
<%@ Page Language="C#" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<html>
<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)));
// 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);
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 Item_Created(Object sender, DataListItemEventArgs e)
{
if (e.Item.ItemType == ListItemType.Item ||
e.Item.ItemType == ListItemType.AlternatingItem)
{
// Retrieve the Label control in the current DataListItem.
Label PriceLabel = (Label)e.Item.FindControl("PriceLabel");
// Retrieve the text of the CurrencyColumn from the DataListItem
// and convert the value to a Double.
Double Price = Convert.ToDouble(
((DataRowView)e.Item.DataItem).Row.ItemArray[2].ToString());
// Format the value as currency and redisplay it in the DataList.
PriceLabel.Text = Price.ToString("c");
}
}
</script>
<body>
<form runat=server>
<h3>DataList ItemCreated Example</h3>
<asp:DataList id="ItemsList"
BorderColor="black"
CellPadding="5"
CellSpacing="5"
RepeatDirection="Vertical"
RepeatLayout="Table"
RepeatColumns="3"
ShowBorder="True"
OnItemCreated="Item_Created"
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:
<asp:Label id="PriceLabel"
runat="server"/>
</ItemTemplate>
</asp:DataList>
</form>
</body>
</html>
<%@ Page Language="VB" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<html>
<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)))
' 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)
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)
' Manually register the event-handling method for the
' ItemCommand event.
AddHandler ItemsList.ItemCreated, AddressOf Item_Created
' 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 Item_Created(sender As Object, e As DataListItemEventArgs)
If e.Item.ItemType = ListItemType.Item Or _
e.Item.ItemType = ListItemType.AlternatingItem Then
' Retrieve the Label control in the current DataListItem.
Dim PriceLabel As Label = CType( _
e.Item.FindControl("PriceLabel"), Label)
' Retrieve the text of the CurrencyColumn from the DataListItem
' and convert the value to a Double.
Dim Price As Double = Convert.ToDouble( _
(CType(e.Item.DataItem, DataRowView)).Row.ItemArray(2).ToString())
' Format the value as currency and redisplay it in the DataList.
PriceLabel.Text = Price.ToString("c")
End If
End Sub
</script>
<body>
<form runat=server>
<h3>DataList ItemCreated Example</h3>
<asp:DataList id="ItemsList"
BorderColor="black"
CellPadding="5"
CellSpacing="5"
RepeatDirection="Vertical"
RepeatLayout="Table"
RepeatColumns="3"
ShowBorder="True"
OnItemCreated="Item_Created"
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:
<asp:Label id="PriceLabel"
runat="server"/>
</ItemTemplate>
</asp:DataList>
</form>
</body>
</html>
<%@ Page Language="C#" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<html>
<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)));
// 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);
dt.Rows.Add(dr);
}
DataView dv = new DataView(dt);
return dv;
}
void Page_Load(Object sender, EventArgs e)
{
// Manually register the event-handling method for the
// ItemCommand event.
ItemsList.ItemCreated +=
new DataListItemEventHandler(this.Item_Created);
// Load sample data only once, when the page is first loaded.
if (!IsPostBack)
{
ItemsList.DataSource = CreateDataSource();
ItemsList.DataBind();
}
}
void Item_Created(Object sender, DataListItemEventArgs e)
{
if (e.Item.ItemType == ListItemType.Item ||
e.Item.ItemType == ListItemType.AlternatingItem)
{
// Retrieve the Label control in the current DataListItem.
Label PriceLabel = (Label)e.Item.FindControl("PriceLabel");
// Retrieve the text of the CurrencyColumn from the DataListItem
// and convert the value to a Double.
Double Price = Convert.ToDouble(
((DataRowView)e.Item.DataItem).Row.ItemArray[2].ToString());
// Format the value as currency and redisplay it in the DataList.
PriceLabel.Text = Price.ToString("c");
}
}
</script>
<body>
<form runat=server>
<h3>DataList ItemCreated Example</h3>
<asp:DataList id="ItemsList"
BorderColor="black"
CellPadding="5"
CellSpacing="5"
RepeatDirection="Vertical"
RepeatLayout="Table"
RepeatColumns="3"
ShowBorder="True"
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:
<asp:Label id="PriceLabel"
runat="server"/>
</ItemTemplate>
</asp:DataList>
</form>
</body>
</html>
平台
Windows 98、Windows 2000 SP4、Windows Server 2003、Windows XP Media Center Edition、Windows XP Professional x64 Edition、Windows XP SP2、Windows XP Starter Edition
.NET Framework 并不是对每个平台的所有版本都提供支持。有关受支持版本的列表，请参见系统要求。
版本信息
.NET Framework
受以下版本支持：2.0、1.1、1.0
请参见
参考
DataList 类
DataList 成员
System.Web.UI.WebControls 命名空间
DataListItemEventHandler
OnItemCreated