[RESOLVED] [02/03] properties and methods of usecontrol

[vishalmarya]

this post should read by those who have used vs 2003.

i have a simple usercontrol with a public sub

   Public sub Setstr() 
        Response.Write("test message")   
  End sub

this usercontrol loads in the comsumer form.

on the button click in consumer form , i make a call to the public procedure

 WebUserControl11.Setstr()

error i get
Object reference not set to an instance of an object .
highlighting "Response.Write("test message") "

[vishalmarya]

anyone trying

same thing works in vs 2005 and not in vs 2003

[neeshu30]

your question is not very clear be precised

[vishalmarya]

your question is not very clear be precised

i have a web user control with a public procedure .

can i call the public procedure from the parent form ?

[mendhak]

Theoretically, you should be able to call the method from your page.

What happens when you replace

Response.Write("test message")

with

Dim x As String = "test"

?

[vishalmarya]

in vs 2003 , when a usercontrol is placed on a web page , we do not get a object instance in code behind file ( .aspx.vb )

it has to be created.

so i did one .

which is like this :

dim WithEvents WebUserControl11 As WebUserControl1

as i am working on a usercontrol for the first time , it didn't struck my mind
it should be protected instead of dim .

so now its working.

i know the basic difference between the two as far as inheritance is concerned , but i don't know how that is affecting my case here ?

[mendhak]

Ah, I had assumed it was created for you. Visual Studio does create it, but there's an intermittent bug in which the control is not declare in the codebehind. My observation is that if you place the control on the page in design view, you have to save it first, and then go to the codebehind.

I don't know what you mean by "affecting my case here." Affecting what?

[vishalmarya]

I don't know what you mean by "affecting my case here." Affecting what?

i started new thread for that

http://www.vbforums.com/showthread.php?t=462242

[vishalmarya]

Ah, I had assumed it was created for you. Visual Studio does create it, but there's an intermittent bug in which the control is not declare in the codebehind. My observation is that if you place the control on the page in design view, you have to save it first, and then go to the codebehind.

after placing the control , i saved the page , build , rebuild , closed and opened it again , still did not got the object in code behind.

i am using .net 1.1 sp1 , vs 2003 sp1

[mendhak]

You're stuck with that then, it's one of the various bugs that were never resolved, AFAIK, with VS 2003. Only a workaround that worked for some.

[vishalmarya]

You're stuck with that then, it's one of the various bugs that were never resolved, AFAIK, with VS 2003. Only a workaround that worked for some.

i don't think it is a bug.
it is supposed be like that only.

a msdn atricle , march 2004 , clearly states that u have to explicitly declare a variable for the usercontrol to use in the code behind.

search for :

"Create a protected member variable in the Web page's code-behind"

in

http://msdn2.microsoft.com/en-us/library/ms972975.aspx

[mendhak]

I was at a Microsoft conference where I spoke to the ASP.NET product manager about this. I am telling you what he told me and his acknowledgment that it is one of those magical features.

Second, it has worked for me in the past while I have not been hallucinating. Additionally, it has worked for others. Therefore, there is a disconnect here. It does not work for you, though, but I have no explanation for it.

Third, that is by Scott Mitchell, so it cannot represent Microsoft's own opinion about the matter.