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)
Visual Basic (Declaration)
<AspNetHostingPermissionAttribute(SecurityAction.InheritanceDemand, Level := AspNetHostingPermissionLevel.Minimal)> _
<AspNetHostingPermissionAttribute(SecurityAction.LinkDemand, Level := AspNetHostingPermissionLevel.Minimal)> _
Public MustInherit Class CompositeDataBoundControl _
Inherits DataBoundControl _
Implements INamingContainer
Dim instance As CompositeDataBoundControl
[AspNetHostingPermissionAttribute(SecurityAction.InheritanceDemand, Level = AspNetHostingPermissionLevel.Minimal)]
[AspNetHostingPermissionAttribute(SecurityAction.LinkDemand, Level = AspNetHostingPermissionLevel.Minimal)]
public abstract class CompositeDataBoundControl : DataBoundControl,
INamingContainer
[AspNetHostingPermissionAttribute(SecurityAction::InheritanceDemand, Level = AspNetHostingPermissionLevel::Minimal)]
[AspNetHostingPermissionAttribute(SecurityAction::LinkDemand, Level = AspNetHostingPermissionLevel::Minimal)]
public ref class CompositeDataBoundControl abstract : public DataBoundControl,
INamingContainer
public abstract class CompositeDataBoundControl extends DataBoundControl implements INamingContainer
<asp:CompositeDataBoundControl />
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).
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.
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
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>");
}
}
}
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
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
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.
.NET Framework
Supported in: 3.5, 3.0, 2.0
Reference