for each loop in Objective-C for accessing NSMutable dictionary

enumeration, key-value, nsdictionary, nsmutabledictionary, objective-c

Solution

for (NSString* key in xyz) {
    id value = xyz[key];
    // do stuff
}

This works for every class that conforms to the NSFastEnumeration protocol (available on 10.5+ and iOS), though `NSDictionary` is one of the few collections which lets you enumerate keys instead of values. I suggest you read about fast enumeration in the Collections Programming Topic.

Oh, I should add however that you should NEVER modify a collection while enumerating through it.

Problem

I am finding some difficulty in accessing mutable dictionary keys and values in Objective-C. Suppose I have this: ``` NSMutableDictionary *xyz=[[NSMutableDictionary alloc] init]; ``` I can set keys and values. Now, I just want to access each key and value, but I don't know the number of keys set. In PHP it is very easy, something as follows: ``` foreach ($xyz as $key => $value) ``` How is it possible in Objective-C?

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