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Andrew Nguyen
2,470 PointsStringing parameters for a method?
Hi, I got a bit confused about this.
In an OOP language such as java a method would be written as:
public int addition(int a, int b){ etc..... }
However, in Objective-C the method would be written as:
-(int)addition:(int)a b:(int)b;
My question is, for the second param b:(int)b , what is the first b before the colon? Is it some place holder or something or are both b's just names? I am a bit confused because the first param is addition:(int)a and the addition is the method name but the first b isn't a method name.
Thanks.
2 Answers
James Andrews
7,245 Points-(int)addition:(int)a withB:(int)b;
Objective-C is considered a self documenting language, so the bit before the : is describing what the next argument is.
The real function name is a concatenation of the descriptors. "addition withB" in the case I've given
It's a weird concept to grasp at first but it makes coding easier imo.
James Andrews
7,245 PointsIt's a descriptor really of what it's expecting, so documenting is one way to put it. Here are a couple of examples of how it would be used.
[MyObject initWithString:@"string" andArray:myArrayObject]; [MyObject initWithString:@"string" andDictionary:myDictionaryObject];
You'll get the idea of it as you move along in the track.
Andrew Nguyen
2,470 PointsAndrew Nguyen
2,470 PointsOhh okay so the bit before the : is just for documentation purposes?