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Shaun Kelly
Shaun Kelly
5,648 Points

-(void) addPoints:(NSInteger)points;

Can somebody please tell me whats the difference between the - and + at the beginning of this line of code ?

1 Answer

  • is an instance method

  • is a class (or static) method.

Methods that begin with '-' can only be called on instances of a class, whereas methods that begin with a '+' are called on the class itself (and thus cannot reference instance variables).

Class methods are often used to perform common tasks that are associated with this data type (for example, the NSString's "stringWithFormat" method), but that are not performed upon instances of that class.