Is there any notice when using Controls property?

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I used Tag property to store an ArrayList of controls, it worked well. But I tried using Controls property instead, with it I can add a control to without needing an ArrayList, I wanted to use Tag property to store others. After changing I can't make my application run as before. I think Controls property may have some special notes to learn. Could you please tell me if it has something noticeable!

Plus, I am suspecting that there is some case that Controls.Add(some control) can't be done successfully!?
Thank you so much!

Posted 7-Apr-11 7:44am

King Boy

Updated 7-Apr-11 8:29am

Sergey Alexandrovich Kryukov

v3

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Sergey Alexandrovich Kryukov 7-Apr-11 14:11pm

OP commented:

I don't think I made some error, simply I have an arraylist named a, after adding needed controls to it by a.Add(...) I do the next step by control1.Tag = a. When changing to using Controls, simply I use control1.Controls.Add(...).
I may not know how it really works!

Sergey Alexandrovich Kryukov 7-Apr-11 14:13pm

@King Boy: please stop posting non-answers as Answer: will be deleted, no one gets e-mail notification.
Thank you.
--SA

[no name] 7-Apr-11 14:21pm

I'm sorry, I am using my mobile phone editing and maybe I'm being so tired of what errors I have made, I intended to type it in comment.

Sergey Alexandrovich Kryukov 7-Apr-11 15:43pm

No problem, I fixed it. Try to post accurately next time, that's it.
--SA

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#realJSOP · Accepted Answer · 2011-04-07T07:51:00

Solution 1

You can add any control to the Controls collection in a form or container.

Chances are that you made some critical errors when you changed over from use the Tag property/ArrayList to using the more appropriate collection (Controls).

Posted 7-Apr-11 7:51am

#realJSOP

v2

Comments

[no name] 7-Apr-11 14:13pm

Could you please show me some the most possible error that I could make?
Thank you so much!

Sergey Alexandrovich Kryukov 7-Apr-11 14:27pm

I think you can find what you did wrong if your read my Answer. You did not provide any code (so how any one can answer what's wrong!), but looking at the text of your Question I can tell: probably ***everything*** is wrong. Well don't provide the code, try to understand my Answer -- it is easy.
--SA

#realJSOP 7-Apr-11 15:13pm

You zigged when you should have zagged. How the hell should I know what you messed up? You're going to have to actually be a programmer (you can google the term if you like), and run your code under the debugger to find out what's wrong.

Sergey Alexandrovich Kryukov 7-Apr-11 14:28pm

John, you see, our friend did not get it (my 5, because you Answer is anyway correct), but by this moment I added my explanation, please see.
--SA

Sergey Alexandrovich Kryukov · Accepted Answer · 2011-04-07T08:25:00

There is no "special notes"! You're trying to misuse properties fundamental to System.Windows.Forms.

The property System.Windows.Forms.Constrol.Controls has most fundamental side effect: the added controls actually appear on the UI (this is a way to add controls to the UI during run time). The added controls become children of the control which Controls property you're using; and the property Parent of each added control is modified accordingly as a result of adding.

You can do it the other way around: if you modify the property Parent of any control, it will immediately jump to a different parent control! If previous value of Parent was null, it will make a control appearing on screen. Automatically, the list of child controls of new parent's Controls property will be modified accordingly.

In contrast, System.Windows.Forms.Constrol.Tag does nothing. It is used just as a container for any objects, very useful as such. Typically, it is used to store some data to be looked up during some event handling. But it does not have to be data; it can be even object, for example, the delegate instance or something as sophisticated :-).

—SA