System.Web.UI.WebControls N ...


.NET Framework Class Library
CompositeDataBoundControl Class

Represents the base class for a tabular data-bound control that is composed of other server controls.

Namespace:  System.Web.UI.WebControls
Assembly:  System.Web (in System.Web.dll)
Syntax

Visual Basic (Declaration)
<AspNetHostingPermissionAttribute(SecurityAction.InheritanceDemand, Level := AspNetHostingPermissionLevel.Minimal)> _
<AspNetHostingPermissionAttribute(SecurityAction.LinkDemand, Level := AspNetHostingPermissionLevel.Minimal)> _
Public MustInherit Class CompositeDataBoundControl _
    Inherits DataBoundControl _
    Implements INamingContainer
Visual Basic (Usage)
Dim instance As CompositeDataBoundControl
C#
[AspNetHostingPermissionAttribute(SecurityAction.InheritanceDemand, Level = AspNetHostingPermissionLevel.Minimal)]
[AspNetHostingPermissionAttribute(SecurityAction.LinkDemand, Level = AspNetHostingPermissionLevel.Minimal)]
public abstract class CompositeDataBoundControl : DataBoundControl, 
    INamingContainer
Visual C++
[AspNetHostingPermissionAttribute(SecurityAction::InheritanceDemand, Level = AspNetHostingPermissionLevel::Minimal)]
[AspNetHostingPermissionAttribute(SecurityAction::LinkDemand, Level = AspNetHostingPermissionLevel::Minimal)]
public ref class CompositeDataBoundControl abstract : public DataBoundControl, 
    INamingContainer
JScript
public abstract class CompositeDataBoundControl extends DataBoundControl implements INamingContainer
ASP.NET
<asp:CompositeDataBoundControl />
Remarks

The CompositeDataBoundControl class serves as the base class for a composite server control that binds to data from a data source. A composite server control is a control that is built from a combination of other server controls. Page developers do not use the CompositeDataBoundControl class directly; instead, they use controls that derive from this class. Examples of composite data-bound controls include the DetailsView, FormView, and GridView controls.

Classes that inherit from the CompositeDataBoundControl control must override the CreateChildControls(IEnumerable, Boolean) method to create the control hierarchy. To access the child controls of a composite data-bound control, use the Controls collection.

Notes to Inheritors:

When you inherit from the CompositeDataBoundControl class, you must override the following member: CreateChildControls(IEnumerable, Boolean).

Examples

The following code example demonstrates how to create a custom composite data-bound control that displays the values of a data source in a table.

Visual Basic
Imports System
Imports System.Collections
Imports System.Data.Common
Imports System.Web.UI
Imports System.Web.UI.WebControls

Namespace Samples.AspNet.VB

    Public Class SimpleSpreadsheetControl
        Inherits CompositeDataBoundControl

        Protected table As New Table()

        Public Overridable ReadOnly Property Rows() As TableRowCollection
            Get
                Return table.Rows
            End Get
        End Property


        Protected Overrides Function CreateChildControls(ByVal dataSource As IEnumerable, ByVal dataBinding As Boolean) As Integer

            Dim count As Integer = 0
            ' If dataSource is not Nothing, iterate through it and
            ' extract each element from it as a row, then
            ' create a SimpleSpreadsheetRow and add it to the
            ' rows collection.
            If Not (dataSource Is Nothing) Then

                Dim row As SimpleSpreadsheetRow
                Dim e As IEnumerator = dataSource.GetEnumerator()

                While e.MoveNext()
                    Dim datarow As Object = e.Current
                    row = New SimpleSpreadsheetRow(count, datarow)
                    Me.Rows.Add(row)
                    count += 1
                End While

                Controls.Add(table)
            End If
            Return count
        End Function 'CreateChildControls
    End Class 'SimpleSpreadsheetControl


    Public Class SimpleSpreadsheetRow
        Inherits TableRow
        Implements IDataItemContainer

        Private dataObj As Object
        Private _itemIndex As Integer

        Public Sub New(ByVal itemIndex As Integer, ByVal o As Object)
            dataObj = o
            _itemIndex = itemIndex
        End Sub 'New

        Public Overridable ReadOnly Property Data() As Object
            Get
                Return dataObj
            End Get
        End Property

        ReadOnly Property DataItem() As Object Implements IDataItemContainer.DataItem
            Get
                Return Data
            End Get
        End Property

        ReadOnly Property DataItemIndex() As Integer Implements IDataItemContainer.DataItemIndex
            Get
                Return _itemIndex
            End Get
        End Property

        ReadOnly Property DisplayIndex() As Integer Implements IDataItemContainer.DisplayIndex
            Get
                Return _itemIndex
            End Get
        End Property
        Protected Overrides Sub RenderContents(ByVal writer As HtmlTextWriter)

            If Not (Data Is Nothing) Then
                If TypeOf Data Is System.Data.Common.DbDataRecord Then
                    Dim temp As DbDataRecord = CType(Data, DbDataRecord)
                    Dim i As Integer

                    While i < temp.FieldCount
                        writer.Write("<TD>")
                        writer.Write(temp.GetValue(i).ToString())
                        writer.Write("</TD>")
                        i += 1
                    End While
                Else
                    writer.Write(("<TD>" + Data.ToString() + "</TD>"))
                End If

            Else
                writer.Write("<TD>This is a test</TD>")
            End If
        End Sub 'RenderContents
    End Class 'SimpleSpreadsheetRow
End Namespace
C#
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>");
        }
    }
}
.NET Framework Security

Inheritance Hierarchy

System..::.Object
  System.Web.UI..::.Control
    System.Web.UI.WebControls..::.WebControl
      System.Web.UI.WebControls..::.BaseDataBoundControl
        System.Web.UI.WebControls..::.DataBoundControl
          System.Web.UI.WebControls..::.CompositeDataBoundControl
            System.Web.UI.WebControls..::.DetailsView
            System.Web.UI.WebControls..::.FormView
            System.Web.UI.WebControls..::.GridView
Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
Platforms

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
Version Information

.NET Framework

Supported in: 3.5, 3.0, 2.0
See Also

Reference

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