Control.AddParsedSubObject Method (System.Web.UI)

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.NET Framework Class Library
Control.AddParsedSubObject Method

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Notifies the server control that an element, either XML or HTML, was parsed, and adds the element to the server control's ControlCollection object.

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

Visual Basic
Protected Overridable Sub AddParsedSubObject ( _
	obj As Object _
)
C#
protected virtual void AddParsedSubObject(
	Object obj
)
Visual C++
protected:
virtual void AddParsedSubObject(
	Object^ obj
)
F#
abstract AddParsedSubObject : 
        obj:Object -> unit 
override AddParsedSubObject : 
        obj:Object -> unit 

Parameters

obj
Type: System.Object

An Object that represents the parsed element.

Remarks

Unless you override it, this method automatically adds LiteralControl objects to the server control's ControlCollection object. This collection is accessible through Control.Controls property.

Examples

The following example is a custom server control that uses the AddParsedSubObject method to determine if elements declared between the opening and closing tags of this control are TextBox Web server controls. If they are, they are added to an ArrayList object, items. When the overridden CreateChildControls method is called, it iterates through the ArrayList and adds each object in it to the ControlCollection of the custom server control.

Security note Security Note

This example has a text box that accepts user input, which is a potential security threat. By default, ASP.NET Web pages validate that user input does not include script or HTML elements. For more information, see Script Exploits Overview.

Visual Basic

' Custom ControlBuilder class. Interprets nested tag name "myitem" as a textbox.
Public Class MyControlBuilder
   Inherits ControlBuilder

   Public Overrides Function GetChildControlType(tagName As String, _
                             attributes As IDictionary) As Type
      If String.Compare(tagName, "myitem", True) = 0 Then
         Return GetType(TextBox)
      End If
      Return Nothing
   End Function
End Class

<ControlBuilderAttribute(GetType(MyControlBuilder))> Public Class MyControl
   Inherits Control
   ' Stores all the controls specified as nested tags.
   Private items As New ArrayList()

   ' This function is internally invoked by IParserAccessor.AddParsedSubObject(Object).
   Protected Overrides Sub AddParsedSubObject(obj As Object)
      If TypeOf obj Is TextBox Then
         items.Add(obj)
      End If
   End Sub

  ' Override 'CreateChildControls'.
   Protected Overrides Sub CreateChildControls()
      Dim myEnumerator As System.Collections.IEnumerator = items.GetEnumerator()
      While myEnumerator.MoveNext()
         Me.Controls.Add(CType(myEnumerator.Current, TextBox))
      End While
   End Sub
End Class


C#

// Custom ControlBuilder class. Interprets nested tag name "myitem" as a textbox. 
public class MyControlBuilder : ControlBuilder 
{
   public override Type GetChildControlType(String tagName,
                                       IDictionary attributes)
   {
      if (String.Compare(tagName, "myitem", true) == 0) 
      {
         return typeof(TextBox);
      }
      return null;
   }
}

[ 
ControlBuilderAttribute(typeof(MyControlBuilder)) 
]
public class MyControl : Control
{
   // Store all the controls specified as nested tags.
   private ArrayList items = new ArrayList();

   // This function is internally invoked by IParserAccessor.AddParsedSubObject(Object).
   protected override void AddParsedSubObject(Object obj) 
   {
      if (obj is TextBox) 
      {
         items.Add(obj);
      }
   }

   // Override 'CreateChildControls'. 
   protected override void CreateChildControls()
   {
      System.Collections.IEnumerator myEnumerator = items.GetEnumerator();
      while(myEnumerator.MoveNext())
          this.Controls.Add((TextBox)myEnumerator.Current);
   }
}    


Version Information

.NET Framework

Supported in: 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0
Platforms

Windows 8 Consumer Preview, Windows Server 8 Beta, Windows 7, Windows Server 2008 SP2, Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

See Also

Reference