"non-standard syntax; use '&' to create a pointer to member" error in Visual Studio 2015

If you use

if (usersList[i]->getUsername() != excludeUser->getUsername)

instead of

if (usersList[i]->getUsername() != excludeUser->getUsername())

your compiler will think you want to use a function pointer instead of the method itself, and if you would have wanted to use a function pointer, you would still have to get the address of it (using &).

So make sure you don't forget your () after a function call!

You are missing the function call parentheses in these lines:

if (usersList[i]->getUsername() != excludeUser->getUsername) {

and

usersNames.append(usersList[i]->getUsername);

Try changing them into this:

if (usersList[i]->getUsername() != excludeUser->getUsername()) {

and

usersNames.append(usersList[i]->getUsername());