Hello
This is nothing but the way of using some oops concepts.
If you want to use the same function in many form with out writing the code ,then just make a class what ever the functions you want to again ,just write all those functions in that class file .where ever you want to use that function ,just create an object of that class file (in which the function is located)
just use that object you can get all the functions in that class file
for example:
//lets class name be classmain in which all your functions exists
//let your form name be form1
where ever you want to use that functions just create object of class like this
classmain objclass=new classmain();
now you can use your objclass in your as many times as needed just by having a dot
objclass.
you will get all the public methods and variables of that class.
Hope you will get the best
Regards
Nmsreddi