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DataList.ItemCreated Event

Definition

Occurs on the server when an item in the DataList control is created.

public:
 event System::Web::UI::WebControls::DataListItemEventHandler ^ ItemCreated;
public event System.Web.UI.WebControls.DataListItemEventHandler ItemCreated;
member this.ItemCreated : System.Web.UI.WebControls.DataListItemEventHandler 
Public Custom Event ItemCreated As DataListItemEventHandler 

Event Type

Examples

The following code example demonstrates how to specify and code a handler for the ItemCreated event to display the order in which items in the DataList control are created.

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)));
 
         // 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>
 
<head runat="server">
    <title>DataList ItemCreated Example</title>
</head>
<body>
 
   <form id="form1" runat="server">

      <h3>DataList ItemCreated Example</h3>
 
      <asp:DataList id="ItemsList"
           BorderColor="black"
           CellPadding="5"
           CellSpacing="5"
           RepeatDirection="Vertical"
           RepeatLayout="Table"
           RepeatColumns="3"
           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" %>
 
<!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)))
 
         ' 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>
 
<head runat="server">
    <title>DataList ItemCreated Example</title>
</head>
<body>
 
   <form id="form1" runat="server">

      <h3>DataList ItemCreated Example</h3>
 
      <asp:DataList id="ItemsList"
           BorderColor="black"
           CellPadding="5"
           CellSpacing="5"
           RepeatDirection="Vertical"
           RepeatLayout="Table"
           RepeatColumns="3"
           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" %>
 
<!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)));
 
         // 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>
 
<head runat="server">
    <title>DataList ItemCreated Example</title>
</head>
<body>
 
   <form id="form1" runat="server">

      <h3>DataList ItemCreated Example</h3>
 
      <asp:DataList id="ItemsList"
           BorderColor="black"
           CellPadding="5"
           CellSpacing="5"
           RepeatDirection="Vertical"
           RepeatLayout="Table"
           RepeatColumns="3"
           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" %>
 
<!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)))
 
         ' 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>
 
<head runat="server">
    <title>DataList ItemCreated Example</title>
</head>
<body>
 
   <form id="form1" runat="server">

      <h3>DataList ItemCreated Example</h3>
 
      <asp:DataList id="ItemsList"
           BorderColor="black"
           CellPadding="5"
           CellSpacing="5"
           RepeatDirection="Vertical"
           RepeatLayout="Table"
           RepeatColumns="3"
           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>

Remarks

The ItemCreated event is raised when an item in the DataList control is created, both during round-trips and at the time data is bound to the control.

The ItemCreated event is commonly used to control the content and appearance of a row in the DataList control.

For more information about handling events, see How to: Consume Events in a Web Forms Application.

Applies to

See also