Does using parameters in methods change anything about the method's function?

I've tried searching google and this site regarding my question but found no answer.

I'm a beginner with Obj-C and would like this question answered.

What is the benefit of using parameters in my methods.

for example..

 -(id)initWithName:(NSString *)newName atFrequency:(double)newFreq { 
self = [super init]; 
if (self != nil) {
name = newName; 
frequency = newFrequency;
} 
return self;
}

versus

 -(void)myMethod {
self = [super init];
if (self != nil) {
name = newName;
frequency = newFreq开发者_Go百科uency;
}
return self;
}

I understand that the -(void) means the method has no return type, and the -(id) means that the first method has 'id' as a return type, and 'id' is generic....

can anyone help explain? I hope my question makes sense, thank you all for your help.

Parameters are inputs to a method, just like function/method parameters in any language. In your second example, on the line frequency = newFrequency;, where is newFrequency supposed to come from?

In other languages, where you might have something like

void initWithName(string newName, double newFreq);

In Obj-C the equivalent is

- (void)initWithName:(NSString *)newName atFrequency:(double)newFreq;

The difference is that in Obj-C, there is an extra piece of the method name for each parameter (like the atFrequency) — in this case, the method name is initWithName:atFrequency:, not just initWithName:.

(This is actually optional, you only have to have a : for each parameter. Technically initWithName:: is still a valid method name, but that's not considered good practice in Obj-C.)

See also:

• How do I pass multiple parameters in Objective-C?
• Is there a language out there in which parameters are placed inside method name?