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IDataItemContainer Interface

Enables data-bound control containers to identify a data item object for simplified data-binding operations.

Namespace: System.Web.UI
Assembly: System.Web (in system.web.dll)
public interface IDataItemContainer : INamingContainer
public interface IDataItemContainer extends INamingContainer
public interface IDataItemContainer extends INamingContainer
Not applicable.

Container classes that implement the IDataItemContainer interface can specify which of their properties identifies the data item for data-binding operations, such as late binding with the DataBinder class.

The following code example demonstrates how to use the IDataItemContainer interface. The SimpleSpreadsheetControl is a control that displays tabular-style data, similar to a DataGrid or GridView control. It contains a set of SimpleSpreadsheetRow objects.

The SimpleSpreadsheetRow class is a container class that implements the IDataItemContainer interface. Although in this example the data item property is intuitively named Data, the DataItem property can be implemented to map to any property or return value of a method.

using System;
using System.Collections;
using System.Data.Common;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace Samples.AspNet.CS
{
    public class SimpleSpreadsheetControl : CompositeDataBoundControl
    {
        protected Table table = new Table();

        public virtual TableRowCollection Rows
        {
            get
            {
                return table.Rows;
            }
        }

        protected override int CreateChildControls(IEnumerable dataSource, bool dataBinding)
        {

            int count = 0;
            // If dataSource is not null, iterate through it and
            // extract each element from it as a row, then
            // create a SimpleSpreadsheetRow and add it to the
            // rows collection.
            if (dataSource != null)
            {

                SimpleSpreadsheetRow row;
                IEnumerator e = dataSource.GetEnumerator();

                while (e.MoveNext())
                {
                    object datarow = e.Current;
                    row = new SimpleSpreadsheetRow(count, datarow);
                    this.Rows.Add(row);
                    ++count;
                }

                Controls.Add(table);
            }
            return count;
        }
    }

    //
    //
    public class SimpleSpreadsheetRow : TableRow, IDataItemContainer
    {
        private object data;
        private int _itemIndex;

        public SimpleSpreadsheetRow(int itemIndex, object o)
        {
            data = o;
            _itemIndex = itemIndex;
        }

        public virtual object Data
        {
            get
            {
                return data;
            }
        }
        object IDataItemContainer.DataItem
        {
            get
            {
                return Data;
            }
        }
        int IDataItemContainer.DataItemIndex
        {
            get
            {
                return _itemIndex;
            }
        }
        int IDataItemContainer.DisplayIndex
        {
            get
            {
                return _itemIndex;
            }
        }
        protected override void RenderContents(HtmlTextWriter writer)
        {

            if (Data != null)
            {
                if (Data is System.Data.Common.DbDataRecord)
                {
                    DbDataRecord temp = (DbDataRecord)Data;
                    for (int i = 0; i < temp.FieldCount; ++i)
                    {
                        writer.Write("<TD>");
                        writer.Write(temp.GetValue(i).ToString());
                        writer.Write("</TD>");
                    }
                }
                else
                    writer.Write("<TD>" + Data.ToString() + "</TD>");
            }

            else
                writer.Write("<TD>This is a test</TD>");
        }
    }
}

The following code example demonstrates how to use the SimpleSpreadsheetControl and AccessDataSource control to display data in an Access database.

<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.CS"
    Assembly="Samples.AspNet.CS"  %>
<%@ Page language="c#" %>
<!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" >
  <head>
    <title>IDataItemContainer - C# Example</title>
  </head>
  <body>
    <form id="Form1" method="post" runat="server">

      <aspSample:SimpleSpreadsheetControl
          id="SimpleSpreadsheet1"
          runat="server"
          datasourceid="AccessDataSource1" />

      <asp:accessdatasource
          id="AccessDataSource1"
          runat="server"
          datasourcemode="DataReader"
          datafile="Northwind.mdb"
          SelectCommand="SELECT OrderID,CustomerID,OrderDate,RequiredDate,
          ShippedDate FROM Orders WHERE EmployeeID = (SELECT EmployeeID 
          FROM Employees WHERE LastName = 'King')">
      </asp:accessdatasource>

    </form>
  </body>
</html>

Windows 98, Windows Server 2000 SP4, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0
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