This is an extension of an earlier post
I have created a custom text box and compiled it and dropped it into my
toolbox. However when I change the value of my custom property in design
mode and switch between design mode to page source and back to design mode
i
am unable to retrieve the property value I set. Also the property setting
in
the html page is lost.
Thsi is the error I get
**********************************
System.Reflection.TargetInvocatonException: Property accessor
'ApplySecurity' on object 'ATextBox2' threw the follwoing exception:
Object
reference not set to an instance of an object~
System.NullReferenceException
--inner stack trace--
System.ComponentModel.ReflectPropertyDescriptor.GetValue(Object component)
System.Windows.Forms.PropertyGridInternal.PropertyDescriptorGridEntry.GetPropertyValueCore(Object
target)
System.Windows.Forms.PropertyGridInternal.PropertyDescriptorGridEntry.get_PropertyValue()
**********************************
Mu source code is
I have added a custom property called ApplySecurity to the html
my custom text box in the page html source of the designer looks like this
<%@ Page Language="C#" AutoEventWireup="true"
CodeFile="AEPFieldDisco.aspx.cs" Inherits="AEPSampleWPD" %>
<%@ Register Assembly="AWebControlLibrary" Namespace="AEPortal"
TagPrefix="cc1" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN"
"
http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="
http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Untitled Page</title>
</head>
<body>
<form id="form1" runat="server">
<cc1:ATextBox ID="ATextBox1" runat="server"
ApplySecurity="True"></cc1:ATextBox>
</form>
</body>
</html>
*********************************************
My text box in the dll has this code
using System;
using System.Collections.Generic;
using System.Text;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.ComponentModel;
using System.Drawing;
namespace AEPortal
{
[ToolboxData("<{0}:ATextBox runat=server
ApplySecurity=True></{0}:ATextBox>")]
public class ATextBox : System.Web.UI.WebControls.TextBox
{
[Bindable(true),
Category("Misc"),
DefaultValue("False")]
string strApplySecurity = null;
public string ApplySecurity
{
get
{
try
{
strApplySecurity = this.Attributes["ApplySecurity"].ToString();
}
catch
{
}
if (strApplySecurity == null)
{
this.Attributes.Add("ApplySecurity", "False");
return "False";
}
else
{
return strApplySecurity;
}
}
set
{
string strTestValue=null;
try
{
strTestValue = this.Attributes["ApplySecurity"].ToString();
}
catch { }
if (strTestValue == null)
{
this.Attributes.Add("ApplySecurity", value);
}
else
{
this.Attributes["ApplySecurity"] = value;
}
}
}
}
}
