How to use a variable of Form2 in Form1, WinForms C#?

Question

I have a solution in Visual Studio 2013 which contains two Forms. I want when a button pressing in Form2, the variable flag_fb is updated and I use its value in For

Answer 1

Something like this should also work.

// Open form2 from form1
using (Form2 form2 = new Form2())          
{
 if (form2.ShowDialog() == DialogResult.OK)
 {

   m_myVal = form2.flag_fb;

 }

}

You should make sure flag_fb is public member variable of Form2, and also make sure it is set to desired value when user clicks OK for instance.