I had posted my problems earlier these days, but seems no one read it. I will reshape my question:

Is there any possibility, in a content page, to load data to the user control that is placed in that content page on the OnPreInit() phase?

By loading data, I mean calling methods from the user control in the content page.

It seems to me that this works on normal web pages, but in content page this is not the case.

I would really appreciate some help.  

If you want to communicate with user control, then you have to expose properties for that.

I created a public function into the user control that should be called somewhere in the contentplaceholder. That function loads some data in the usercontrol and on the OnLoad of the usercontrol i draw some dynamic controls. The problem that i have is that by calling that public function in the OnPreInit of the contentplaceholder, i get a null pointer exception, the user control doesn't exist, yet.

That is my problem :|

DaeMoohn:

I created a public function into the user control that should be called somewhere in the contentplaceholder. That function loads some data in the usercontrol and on the OnLoad of the usercontrol i draw some dynamic controls. The problem that i have is that by calling that public function in the OnPreInit of the contentplaceholder, i get a null pointer exception, the user control doesn't exist, yet.

 

That is my problem :|

Hi DaeMoohn,

See the following article:

http://www.codeproject.com/useritems/lifecycle.asp,

And see the following paragraphs:

It is important to note that Master Page is treated like a control in the Content Pages.
So if a Page has a  Master Page associated with it, then the controls on the page will not be initialized and would be null in this stage. Only after the Init() event starts, you can access these controls directly from the page class. Why?

The reason being that all controls placed in the Content Page are within a ContentPlaceholder which is a child control of a MasterPage. Now Master Page is merged and treated like a control in the Content Pages. As I mentioned earlier, all events except the Init() and Unload() are fired from outermost to the innermost control. So PreInit() in the Page is the first event to fire but User Controls or MasterPage (which is itself a Usercontrol) do not have any PreInit event . Therefore in the Page_PreInit() method, neither the MasterPage nor any user control has been initialized and only the controls inside the Page class are set to their default values. Only after the Page_PreInit() event the Init() events of other controls fire up.

Hope it helps,

Hong Gang

Thank you