title: Check if all characters are uppercase in string - Obj C
body: <p>I know I can check if a string <em>contains</em> uppercase letters but is there some built in function in Objective-C to check if <em>all</em> characters are uppercase letters? I want to avoid looping through each character to see if it contains a lowercase letter and then break out of the loop if it contains one as this takes up more memory and takes more time. Time is a constraint as I have to process thousands of strings.</p>