How to use local and global variables

A global variable is visible in all methods of a given class.
A local variable is only visible in its particular method.
You may wish to prefix global variables with a character such as "$" to differentiate them.

To make global variables that can be accessed by all the classes of a project, declare them as public in one of your modules (for example, a module called "Global") and then refer to them as properties of that module (for example, Global.myvariable).

The Program:

Button1 writes "tea with milk" in Label1
Button2 writes "tea with sugar" in Label2
"tea with " is global,
"milk" and "sugar" are local.

The Code:

' Gambas class file

X AS String
X is global
'it`s NOT allowed to define a value here
'but it can be done in the constructor _new()
'try this instead:
'CONST X AS String = "tea with "
PUBLIC SUB _new()
  X = "tea with "
END

STATIC PUBLIC SUB Main()
  DIM hForm AS Fmain
  hForm = NEW Fmain
  hForm.show
END

PUBLIC SUB Button1_Click()
  DIM Y AS String
  Y = "milk"
  
'Y is local
  Label1.Text= X & Y
END

PUBLIC SUB Button2_Click()
  DIM Y AS String
  Y = "sugar"
  Label2.Text= X & Y
END
'you see the variables X and Y are different:
'each is visible only in its particular method

The Source

Download



Referenced by :