A function that return the values of all attributes

Question

Is it possible to give an instance of object to a function and the function return the value of all attributes for this instance ?? the function should work for any class

Note that such a code is usually just a workaround for bad architecture. Although it is often useful for debugging or testing. — Sulthan, May 26 '13 at 15:19
What @Sulthan said. If this code and the answers to your other questions are used beyond debugging or pure academic curiosity, you are heading down a path that will produce a very difficult, very fragile, codebase. Objective-C was simply not designed for this level of introspection based programming. — bbum, May 26 '13 at 18:07

Burhanuddin Sunelwala · Accepted Answer · 2013-05-26T15:47:42.660

2

This is the solution:

unsigned int numberOfAttributs;
objc_property_t *attributes = class_copyPropertyList([obj class], &numberOfAttributes);

for (unsigned int i = 0; i < numberOfAttributes; i++) {

    objc_property_t attribute = attributes[i];  
    NSString *attributeName = [NSString stringWithUTF8String: property_getName(attribute)];
    NSLog(@"%@", attributeName);
    id attributeValue = [obj valueForKey:attributeName];
    NSLog(@"%@", attributeValue);
}

edited May 26 '13 at 15:47

answered May 26 '13 at 14:16

Burhanuddin Sunelwala

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for value, you could try:- [obj valueForKey:@"property_getName(attribute)"]; Try it and then let me know the success – Burhanuddin Sunelwala May 26 '13 at 14:35
you can add a check and check for type of variable! – Burhanuddin Sunelwala May 26 '13 at 14:45
@bbum `valueForKey` will always return an object, even if it's a `NSValue`. – Sulthan May 26 '13 at 14:56
I have fixed the types to `unsigned` and the first parameter of `class_copyPropertyList`. – Sulthan May 26 '13 at 14:58
property_getName return a 'const char *' not an NSString, so this answer will crash ... – Emmanuel May 26 '13 at 15:42
Note that this is going to barf on properties that return structs and it is also going to miss any setter/getter pairs that are not declared as @property. – bbum May 26 '13 at 18:08

A function that return the values of all attributes

1 Answers1