How to control the Form components from the other Units

Microsoft Visual C++ 2008

My Project contains one Form1 and one Unit (module) Test1.cpp.
There is the button1 on the Form1 which calls the function:

Code:

---

Test1::Change_Button_Text();

---

There is only one function in unit Test1.cpp

Code:

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void Test1::Change_Button_Text()
{
        // #1
        Form1::button1->Text = "Hello forum!"; // isn't working :(
 
        // #2
        Form1 ^fr1 = gcnew Form1();
        fr1->button1->Text = "Hello Forum!" // isn't working :(
}

---

What I want: Run the project, click the button and the button text will be changed to "Hello Forum!".

This is targeted to the following task: to find the way how to control Form properties (and Form component properties) from the other Units (Modules) of the Project (not only from the Form1.h).

I'm going to write a lot of procedures and do not want to place them in Form1.h header.

Thank you!
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P.S.
I cannot post here my example, but you can download it here (Test1.zip on the page buttom):
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