Difference between NSString literals

Question

What is the difference between these two lines?

NSString * string = @\"My String\";
NSString * string = [[[NSString alloc] initWithString:@\"MyString\"] auto         


        

Answer 1

Just remember this basic thing:-

NSString *string = ...

This is a pointer to an object, "not an object"!

Therefore, the statement: NSString *string = @"Hello"; assigns the address of @"Hello" object to the pointer string.

@"Hello" is interpreted as a constant string by the compiler and the compiler itself allocates the memory for it.

Similarly, the statment

NSObject *myObject = somethingElse;

assigns the address of somethingElse to pointer myObject, and that somethingElse should already be allocated ad initialised.

Therefore, the statement: NSObject *myObject = [[NSObject alloc] init]; allocates and initializes a NSObject object and assigns its address to myObject.