What does the ^ operator do to a BOOL?

问题

What does this statement mean?

isChecked = isChecked ^ 1;

isChecked is a BOOL.

回答1:

it will XOR isChecked with 1 so I suppose true ^ 1 = 0(false) and false ^1 = 1(true)

回答2:

The "^" is an exclusive OR operation, so 0 flips to 1, and 1 flips to zero. The result should be the same as isChecked = !isChecked.

回答3:

It only flips the last bit of BOOL. Not a reliable way to logically negate. If someone is crazy enough to set the a BOOL variable to some number, for example 5. Then doing ^ 1 will only flip the last bit of the value to 4, which is still evaluated to YES.

If you want to logically negate, use ! operator instead.

回答4:

Everyone is saying it XORs the bool-- that's true-- but the purpose here is that it's toggling the bool.

The advantage of doing a bitwise toggle like this is speed and the ability to fiddle bits in extreme detail.

for more Bitwise Operators

回答5:

^ is the exclusive or operator.

In your example it is used to create a toggle - isChecked will be set only if isChecked was previously unset.

回答6:

"^" is called an exclusive OR or XOR operation. In this case, it will change boolean from true to false and vice-versa.

To learn more on this, check this link

回答7:

this is bitwise XOR operator and changes 0 to 1, and 1 to zero. see all opertors here.

来源：https://stackoverflow.com/questions/10793720/what-does-the-operator-do-to-a-bool