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LinkButton.AddParsedSubObject(Object) Method

Definition

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

protected:
 override void AddParsedSubObject(System::Object ^ obj);
protected override void AddParsedSubObject (object obj);
override this.AddParsedSubObject : obj -> unit
Protected Overrides Sub AddParsedSubObject (obj As Object)

Parameters

obj
Object

An Object that represents the parsed element.

Examples

The following code example demonstrates how to override the AddParsedSubObject method in a custom LinkButton server control so that it either sets the text property to the parsed object's text property, if the parsed object is a Literal object, or to an empty string otherwise.

<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.CS.Controls" Assembly="Samples.AspNet.CS" %>
<%@ Page Language="C#" AutoEventWireup="True" %>
<!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>Custom LinkButton - AddParsedSubObject - C# Example</title>
    <script runat="server">
      void LinkButton1_Command(Object sender, CommandEventArgs e) 
      {
        // Redirect to the Microsoft home page.
        Response.Redirect("http://www.microsoft.com/");
      }
    </script>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom LinkButton - AddParsedSubObject - C# Example</h3>
            
            <aspSample:CustomLinkButtonAddParsedSubObject 
              id="LinkButton1" 
              runat="server" 
              OnCommand="LinkButton1_Command" 
              ToolTip="Microsoft Home">Microsoft Corp.
            </aspSample:CustomLinkButtonAddParsedSubObject>

        </form>
    </body>
</html>
<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.VS.Controls" Assembly="Samples.AspNet.VB" %>
<%@ Page Language="VB" AutoEventWireup="True" %>
<!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>Custom LinkButton - AddParsedSubObject - VB.NET Example</title>
        <script runat="server">
            Sub LinkButton1_Command(sender As Object, e As CommandEventArgs)
                ' Redirect to the Microsoft home page.
                Response.Redirect("http://www.microsoft.com/")
            End Sub
        </script>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom LinkButton - AddParsedSubObject - VB.NET Example</h3>
            
            <aspSample:CustomLinkButtonAddParsedSubObject id="LinkButton1" 
             runat="server" OnCommand="LinkButton1_Command" 
             ToolTip="Microsoft Home">Microsoft Corp.</aspSample:CustomLinkButtonAddParsedSubObject>

        </form>
    </body>
</html>
using System.Web;
using System.Security.Permissions;

namespace Samples.AspNet.CS.Controls
{
    [AspNetHostingPermission(SecurityAction.Demand, Level = AspNetHostingPermissionLevel.Minimal)]
    public sealed class CustomLinkButtonAddParsedSubObject : System.Web.UI.WebControls.LinkButton
    {
        protected override void AddParsedSubObject(object obj)
        {
            // If the server control contains any child controls.
            if (this.HasControls()) 
            {
                // Notify the base server control that an element, either XML or HTML, 
                // was parsed, and adds the element to the server control's 
                // ControlCollection object.
                base.AddParsedSubObject(obj);
            }
            else // Else the server control doesn't contain any child controls.
            {
                // If the parsed element is a LiteralControl.
                if (obj is System.Web.UI.LiteralControl) 
                {
                    // Set the server control's Text property to the parsed element's Text value.
                    this.Text = ((System.Web.UI.LiteralControl)obj).Text;
                }
                else // Else the parsed element is not a LiteralControl.
                {
                    // If the server control has a value in the Text property.
                    string currentText = this.Text;
                    if (currentText.Length != 0) 
                    {
                        // Set the server control's Text property to an empty string.
                        this.Text = System.String.Empty;

                        // Notify the base server control that a new LiteralControl was parsed, 
                        // and adds the element to the server control's ControlCollection object.
                        base.AddParsedSubObject(new System.Web.UI.LiteralControl(currentText));
                    }
                    base.AddParsedSubObject(obj);
                }
            }
        }
    }
}
<AspNetHostingPermission(SecurityAction.Demand, Level:=AspNetHostingPermissionLevel.Minimal)> _
Public NotInheritable Class CustomLinkButtonAddParsedSubObject
    Inherits System.Web.UI.WebControls.LinkButton

    Protected Overrides Sub AddParsedSubObject(ByVal obj As Object)

        ' If the server control contains any child controls.
        If Me.HasControls() Then

            ' Notify the base server control that an element, either XML or HTML, 
            ' was parsed, and adds the element to the server control's 
            ' ControlCollection object.
            MyBase.AddParsedSubObject(obj)
            ' Else the server control doesn't contain any child controls.
        Else
            ' If the parsed element is a LiteralControl.
            If TypeOf obj Is System.Web.UI.LiteralControl Then

                ' Set the server control's Text property to the parsed element's Text value.
                Me.Text = CType(obj, System.Web.UI.LiteralControl).Text

                ' Else the parsed element is not a LiteralControl.
            Else
                ' If the server control has a value in the Text property.
                Dim currentText As String = Me.Text
                If currentText.Length <> 0 Then

                    ' Set the server control's Text property to an empty string.
                    Me.Text = System.String.Empty

                    ' Notify the base server control that a new LiteralControl was parsed, 
                    ' and adds the element to the server control's ControlCollection object.
                    MyBase.AddParsedSubObject(New System.Web.UI.LiteralControl(currentText))
                End If
                MyBase.AddParsedSubObject(obj)
            End If
        End If
    End Sub
End Class

Applies to

See also