Control.AddParsedSubObject(Object) Method
Definition
Important
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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.
protected:
virtual void AddParsedSubObject(System::Object ^ obj);
protected virtual void AddParsedSubObject (object obj);
abstract member AddParsedSubObject : obj -> unit
override this.AddParsedSubObject : obj -> unit
Protected Overridable Sub AddParsedSubObject (obj As Object)
Parameters
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.
Important
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.
// 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);
}
}
' 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
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.