Language Reference |
Used to increment a variable by a specified amount.
result += expression
The += operator syntax has these parts:
Part Description result Any variable. expression Any expression.
Using this operator is exactly the same as specifying:The underlying subtype of the expressions determines the behavior of the += operator.result = result + expression
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.
For information on when a run-time error is generated by the += operator, see the Operator Behavior table.