How do I split a string into an array of characters with Swift?

Question

I am new to iOS programming with Swift. I have stored a string in the variable stringlength.

Let's say...

var stringlength = "Hello"

How do I split this to an array of characters?

Example: ["H", "e", "l", "l", "o"]

In Java I know that toCharArray() works but what do I do in Swift? I have looked everywhere online.

Thanks in advance.