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Addition Operator (+) (VBScript) 

Sums two numbers.


result = expression1 + expression2

Arguments

  • result
    Any numeric variable.
  • expression1
    Any expression.
  • expression2
    Any expression.

Remarks

Although you can also use the + operator to concatenate two character strings, you should use the & operator for concatenation to eliminate ambiguity and provide self-documenting code.

When you use the + operator, you may not be able to determine whether addition or string concatenation will occur.

The underlying subtype of the expressions determines the behavior of the + operator in the following way:

If Then

Both expressions are numeric

Add.

Both expressions are strings

Concatenate.

One expression is numeric and the other is a string

Add.

If one or both expressions are Null expressions, result is Null. If both expressions are Empty, result is an Integer subtype. However, if only one expression is Empty, the other expression is returned unchanged as result.

Requirements

Version 1

See Also

Reference

Concatenation Operator (&)
Subtraction Operator (-) (VBScript)
Operator Precedence (VBScript)

Concepts

Arithmetic Operators
Concatenation Operators

Other Resources

Operator Summary (VBScript)