result

Any variable.

expression

Any expression.

Using this operator is exactly the same as specifying:

 	Copy Code
result = result & expression

The &= operator looks at the binary representation of the values of result and expression and does a bitwise AND operation on them. The output of this operation behaves like this:

 	Copy Code
0101 (result) 1100 (expression) ---- 0100 (output)

Any time both of the expressions have a 1 in a digit, the result has a 1 in that digit. Otherwise, the result has a 0 in that digit.

Version 1

Reference

Concepts