Passing a variable from one form to another without creating a new instance of the first form

Noah NU

Let's say I have form1 and form2. Form1 and Form2 are open. You click a button on Form2 and it adds 1 to a variable called myNumber on Form1.

Now the problem is I can't use the new keyword and create a new instance of Form1, because Form1 declares myNumber setting it to 0 on creation of the form. If myNumber gets set to 0 again then all the 1's that were added to that variable were added for nothing....

How do I pass a variable from Form2 to Form1 without creating a new instance of Form1?

3 Replies

Know the answer? Post it — somebody with the same question will find it here.

Sam Hobbs16y ago
Again back to my answer. It is extremely easy if you are familiar with the basics.

You said "pass a variable from Form2 to Form1"; if my answer won't work then you need to clarify your question, not criticize my attempt to help.

I think you don't understand what is meant by "a public member"; why do you say it won't work?
Noah NU16y ago
A public member wouldn't work. It has to be after showing Form2.. Since a button will be clicked. A VISIBLE button. The value must be set after the the form is shown...
So again back to my question.
Sam Hobbs16y ago
The answer is extremely easy for anyone familiar with the basics of C#.

Just create a public member in Form2 and after creating an insance of Form2 but before showing it, set the public member to the value to be passed. In the Form2 load event, use the public member.