Random Alphanumeric String Linux Swift 3

Question

Im having 2 problems when trying to generate a random string in Linux with Swift 3.

1. arc4random_uniform is not available in Linux only on BSD. SO i was able

Answer 1

I copied and pasted your code exactly, and it doesn't compile.

fatal error: Can't form a Character from an empty String

Here's an alternative method:

// Keep at top of your code (outside of functions)
#if os(Linux)
    srandom(UInt32(time(nil)))
#endif


func getRandomNumber(_ min: Int, _ max: Int) -> Int {
    #if os(Linux)
        return Int(random() % max) + min
    #else
        return Int(arc4random_uniform(UInt32(max)) + UInt32(min))
    #endif
}


func getRandomString(_ chars: String, _ length: Int) -> String {
    var str = ""

    for _ in 1...length {
        str.append(chars.itemOnStartIndex(advancedBy: getRandomNumber(0, chars.count - 1)))
    }

    return str
}


// Best practice to define this outside of the function itself
let chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
print(getRandomString(chars, 10))

This works for me on Ubuntu.