Microsoft® Visual Basic® Scripting Edition Xor Operator 
Language Reference Version 1

Used to perform a logical exclusion on two expressions.
result = expression1 Xor expression2The Xor operator syntax has these parts:
Part Description result Any numeric variable. expression1 Any expression. expression2 Any expression.
If one, and only one, of the expressions evaluates to True, result is True. However, if either expression is Null, result is also Null. When neither expression is Null, result is determined according to the following table:
The Xor operator also performs a bitwise comparison of identically positioned bits in two numeric expressions and sets the corresponding bit in result according to the following table:
If expression1 is And expression2 is Then result is True True False True False True False True True False False False
If bit in expression1 is And bit in expression2 is Then result is 0 0 0 0 1 1 1 0 1 1 1 0