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DataList.ItemStyle Property

Definition

Gets the style properties for the items in the DataList control.

public:
 virtual property System::Web::UI::WebControls::TableItemStyle ^ ItemStyle { System::Web::UI::WebControls::TableItemStyle ^ get(); };
[System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerProperty)]
public virtual System.Web.UI.WebControls.TableItemStyle ItemStyle { get; }
[<System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerProperty)>]
member this.ItemStyle : System.Web.UI.WebControls.TableItemStyle
Public Overridable ReadOnly Property ItemStyle As TableItemStyle

Property Value

A TableItemStyle object that contains the style properties for the items in the DataList control. The default value is an empty TableItemStyle object.

Attributes

Examples

The following code example demonstrates how to use the ItemStyle property to specify a different background color for 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 Selection_Change(Object sender, EventArgs e)
      {

         // Set the background color for the heading and footer sections
         // of the DataList control.
         ItemsList.ItemStyle.BackColor = 
             System.Drawing.Color.FromName(ItemList.SelectedItem.Value);
         ItemsList.AlternatingItemStyle.BackColor = 
             System.Drawing.Color.FromName(AltItemList.SelectedItem.Value);

      }
 
   </script>
 
<head runat="server">
    <title>DataList ItemStyle and AlternatingItemStyle Example</title>
</head>
<body>
 
   <form id="form1" runat="server">

      <h3>DataList ItemStyle and AlternatingItemStyle Example</h3>

      Select background colors for the items and alternating items.

      <br /><br />
 
      <asp:DataList id="ItemsList"
           BorderColor="black"
           CellPadding="5"
           CellSpacing="5"
           RepeatDirection="Vertical"
           RepeatLayout="Table"
           RepeatColumns="3"
           ShowFooter="True"
           runat="server">

         <HeaderStyle BackColor="#aaaadd">
         </HeaderStyle>

         <ItemStyle BackColor="White">
         </ItemStyle>

         <AlternatingItemStyle BackColor="White">
         </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>

         <AlternatingItemTemplate>

            <asp:Image id="ProductImage"
                 AlternatingText='<%# DataBinder.Eval(Container.DataItem, "StringValue") %>'
                 ImageUrl='<%# DataBinder.Eval(Container.DataItem, "ImageValue") %>'
                 runat="server"/>

            <br />

            Description: <br />
            <%# DataBinder.Eval(Container.DataItem, "StringValue") %>

            <br />

            Price: <%# DataBinder.Eval(Container.DataItem, "CurrencyValue", "{0:c}") %>       

         </AlternatingItemTemplate>
 
      </asp:DataList>

      <hr />

      <table cellpadding="5">

         <tr>

            <td>

               Item BackColor:
 
            </td>

            <td>

               Alternating item BackColor:

            </td>

         </tr>

         <tr>

            <td>

               <asp:DropDownList id="ItemList"
                    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>

            <td>

               <asp:DropDownList id="AltItemList"
                    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" %>
 
<!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 Selection_Change(sender As Object, e As EventArgs)

         ' Set the background color for the heading and footer sections
         ' of the DataList control.
         ItemsList.ItemStyle.BackColor = _
             System.Drawing.Color.FromName(ItemList.SelectedItem.Value)
         ItemsList.AlternatingItemStyle.BackColor = _
             System.Drawing.Color.FromName(AltItemList.SelectedItem.Value)

      End Sub
 
   </script>
 
<head runat="server">
    <title>DataList ItemStyle and AlternatingItemStyle Example</title>
</head>
<body>
 
   <form id="form1" runat="server">

      <h3>DataList ItemStyle and AlternatingItemStyle Example</h3>

      Select background colors for the items and alternating items.

      <br /><br />
 
      <asp:DataList id="ItemsList"
           BorderColor="black"
           CellPadding="5"
           CellSpacing="5"
           RepeatDirection="Vertical"
           RepeatLayout="Table"
           RepeatColumns="3"
           ShowFooter="True"
           runat="server">

         <HeaderStyle BackColor="#aaaadd">
         </HeaderStyle>

         <ItemStyle BackColor="White">
         </ItemStyle>

         <AlternatingItemStyle BackColor="White">
         </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>

            <td>

               Item BackColor:
 
            </td>

            <td>

               Alternating item BackColor:

            </td>

         </tr>

         <tr>

            <td>

               <asp:DropDownList id="ItemList"
                    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>

            <td>

               <asp:DropDownList id="AltItemList"
                    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>

Remarks

Use this property to provide a custom style for the items of the DataList control. Common style attributes that can be adjusted include foreground color, background color, font, and content alignment within the cell. Providing a different style enhances the appearance of the DataList control.

Item style properties in the DataList control are inherited from one item style property to another through a hierarchy. Item style properties set lower in the hierarchy are inherited by item style properties higher in the hierarchy. For example, if you specify a red font for the ItemStyle property, all other item style properties in the DataList control will also have a red font. This allows you to provide a common appearance for the control by setting a single item style property. You can override the inherited style settings for an item style property that is higher in the hierarchy by setting its style properties. For example, you can specify a blue font for the AlternatingItemStyle property, overriding the red font specified in the ItemStyle property. The following table lists the hierarchy order from highest to lowest.

Precedence Style Property
1 EditItemStyle
2 SelectedItemStyle
3 AlternatingItemStyle
4 ItemStyle
5 ControlStyle

To specify a custom style for the items of the DataList control, place the <ItemStyle> tags between the opening and closing tags of the DataList control. You can then list the style attributes within the opening <ItemStyle> tag.

You can also use the AlternatingItemStyle property to provide a different appearance for the alternating items in the DataList control.

Applies to

See also