Detect Open Forms

[cabUK]

I am new to VB.net and I am currently writing a program that has a couple of forms which can be accessed through a menu.

What I need to do is when someone presses the button on the menu to show the form I want to be able to detect if there is already one of the forms open.

i seem to be having a bit of trouble getting this so any adivce or tips would be much appreciated.

thanks

Craig