User Defined Functions in VBScript

User Defined Functions
==========================
1. Defining a Function without arguments

Syntax:

Function <function name>()
   Statements
End Function

Eg: Adding two numbers

Difining Function
-----------------------
Function Sum()
   a=10
   b=20
   c=a+b
print c
End Function

Calling Function
------------------------
1. Using Call method
eg:
Call Sum()

2. Without Call method
eg:
Sum()

3. using variable

x=Sum()

Example
------------------------
Function sum(x, y)
     print x+y
End Function


Call sum(10,20)
Call sum(5,9)


To View Local Functions
--------------------------------------
View -> Toolbox




Types of Arguments
----------------------------
1. ByVal : It refers the value

2. ByRef : It refers the memory location. By default argument type is ByRef.

Example
---------------
Function Sample(Byval a, Byref b,c)
a=100
b=200
c=300

End Function

a=10
b=20
c=30
Call sample(a,b,c)
msgbox a
msgbox b
msgbox c

Note:
----------
You will get output

10
200
300

a is ByVal. So, which value is there that you will get.  b and c are ByRef, so it takes values from where you defined in funtion.

Example
----------------------`
Function Sum(a,b,c)
     c=a+b
End Function

Call sum(2,3,c)
msgbox c