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Addition Assignment Operator (+=)

Adds the value of an expression to the value of a variable and assigns the result to the variable.

result += expression 

Arguments

result
Any variable.
expression
Any expression.

Remarks

Using this operator is exactly the same as specifying:

result = result + expression

The underlying subtype of the expressions determines the behavior of the += operator.

If Then
Both expressions are numeric or Boolean Add
Both expressions are strings Concatenate
One expression is numeric and the other is a string Concatenate

Requirements

Version 1

See Also

+ Operator | Operator Precedence | Operator Summary