ref and out Values

Any function, in any context, may have ref and/or out arguments. They are just additional tools to help a programmer express their ideas in code.

Any individual argument may be ref, out, or neither:

An argument that's neither ref nor out is purely an input to the function.
An argument that's out is purely an output from the function.
An argument that's ref is both an input and output.

Here is a script transaction that demonstrates the three cases:

transaction 1 script 'New script transaction'
{
    	void f(int x, ref int y, out int z)
    	{
    	Print(); 
             PrintFormat("       Just entered f: x = {0}, y = {1}, z = {2}.", x, y, z);
             x += 10;
             y += 10;
             y += 10;
             Print();
             PrintFormat("       About to return from f: x = {0}, y = {1}, z = {2}.", x, y, z);
             }
             int a = 1, b = 2, c = 3;
             Print();
             PrintFormat("Before calling f: a = {0}, b = {1}, c = {2}", a, b, c);
             f(a, ref b, out c);
            Print();
            PrintFormat("After calling f: a = {0}, b = {1}, c = {2}", a, b, c); 
}

When this transaction is run, it prints the following output to the script console:

Before calling f: a = 1, b = 2, c = 3
	Just entered f: x = 1, y = 2, z = 0.
	About to return from f: x = 11, y = 12, z = 10.
After calling f: a = 1, b = 12, c = 10

To open the console window, you must navigate through the ribbon and select the (Script Console ).