In Objective-C, you can get the value of a specific key of a hash (NSDictionary) using the objectForKey: method. Here is an example:
``objective-c
NSDictionary *myDict = @{ @"key1": @"value1", @"key2": @"value2", @"key3": @"value3" };
NSString *valueForKey2 = [myDict objectForKey:@"key2"];
NSLog(@"The value for key2 is: %@", valueForKey2);
In the above example, we create an NSDictionary object named with three key-value pairs. We then use the objectForKey: method to get the value associated with the key "key2" and store it in a variable named valueForKey2. Finally, we print the value of valueForKey2 using NSLog.
The output of the above code will be:
The value for key2 is: value2
Alternatively, you can also use the modern Objective-C syntax using the square bracket notation for accessing elements:
NSDictionary *myDict = @{ @"key1": @"value1", @"key2": @"value2", @"key3": @"value3" };
NSString *valueForKey2 = myDict[@"key2"];
NSLog(@"The value for key2 is: %@", valueForKey2);
``
The output of this code will be the same as the previous example.