how to get the value of a control if it 's handle is zero?

Question

I've known that a control gets its handle when it can be seen the first time.
My problem is that in my program , I want to get the value of a control in anther forms(not created by me).When I use the API "ChildWindowFormPointEx" , it returns zero--it hasn't been seen ever--so I can't get it .
Who can help me? Thanks in advance!

PJ Martins · Answer

do you know if this program was written in .NET?

du lading · Answer

Thank you for your answer. The form is created in another programso I don't know about the name of the form. BesidesI could only get the handle of the form .Could I use Form.Controls to loop? If yes  how can do it?I really have no idea. Hoping for your answer!

PJ Martins · Answer

If you know the name of the control you can simply try to find it through the Form.Controls.Find method. If you do not know the name you'll have to loop through the Form.Controls collection and search the control by type.