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Author Simple newbie question
Griff

2005-03-16, 4:06 pm

How do I get to the Class object for an Instance variable ?

Thing * myThing;
myThing = [[Thing alloc] init];

ie, I can access the name of the Thing class with

[Thing class]

or, from within instance methods of the Thing class I can access "isa"

BUT if I am iterating through an Array and I encounter "myThing", what
message can I send to "myThing" to get to the [Thing class] info ?

Thanks,

Griff
Christian Brunschen

2005-03-16, 4:06 pm

In article <d698d3e7.0502151054.27828fb2@posting.google.com>,
Griff <griffph@aol.com> wrote:
>How do I get to the Class object for an Instance variable ?
>
>Thing * myThing;
>myThing = [[Thing alloc] init];
>
>ie, I can access the name of the Thing class with
>
>[Thing class]
>
>or, from within instance methods of the Thing class I can access "isa"
>
>BUT if I am iterating through an Array and I encounter "myThing", what
>message can I send to "myThing" to get to the [Thing class] info ?


Simple: there is an instance method

- class;

that returns the class object for a given instance. So, you would write

Class someClass = [myThing class];

to retrieve the class of which 'myThing' is an instance.

All of this is documented in the documentation for the NSObject class and
the NSObject protocol.

>Thanks,


Best wishes,

>Griff


// Christian Brunschen
Griff

2005-03-16, 4:06 pm

Well, duh!

Yeah, that works..!

Thanks very much Christian :-)
Christian Brunschen

2005-03-16, 4:06 pm

In article <d698d3e7.0502160233.6f92b14a@posting.google.com>,
Griff <griffph@aol.com> wrote:
>Well, duh!
>
>Yeah, that works..!
>
>Thanks very much Christian :-)


You're most welcome :)

Best wishes,

// Christian Brunschen

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