how to connect module to form without recodeing

hello
i make a form with a very long code then i want to take some code to anther file(class , modules,...)
but without re-code for example
code in form is: "if textbox1.text="yes""
the code in modules must be :"if form1.textbox1.text="yes""

is there is any way to use the 1st code in module or classe or....


thank you