Here is the test function:

func testString(string : String)
{
    var result : Int
       println("Testing \"\(string)\"")
    result = string.bridgeToObjectiveC().length
       println("string.bridgeToObjectiveC().length : \(result)")
    result = (string as NSString).length
       println("(string as NSString).length : \(result)")
    result = countElements(string)
       println("countElements(string) : \(result)")
    result = string.lengthOfBytesUsingEncoding(NSUTF8StringEncoding)
       println("string.lengthOfBytesUsingEncoding(NSUTF8StringEncoding) : \(result)")
    result = string.lengthOfBytesUsingEncoding(NSUTF16StringEncoding)
       println("string.lengthOfBytesUsingEncoding(NSUTF16StringEncoding) : \(result)")
    result = string.utf16count
       println("string.utf16count : \(result)")
    var manager = NSLayoutManager()
    let storage = NSTextStorage(string:string)
    manager.textStorage = storage
    result = manager.numberOfGlyphs
       println("layoutManager.numberOfGlyphs : \(result)")
       println("")
}

Here are the results. (It’s a picture not text because my CMS kept barfing at the special characters. Sorry.)

This snippet by Fishrock123,  on the other hand, is just awesome. As he describes it, the code “[c]ounts the average byte length in a unicode string. (lol)”

Thanks especially to Simon Yang, August Joki, Phil Holland, Daniel Jalkut, Ken Ferry, Fishrock123 (Jeremiah Senkpiel)