swift 判断 密码 包含字母和数字 最多只有6-16位数

func isPassWord(string: String) {

     let allRegex:NSPredicate = NSPredicate(format: "SELF MATCHES %@", "^[\\x21-\\x7E]{6,16}$")

      let numberRegex:NSPredicate = NSPredicate(format: "SELF MATCHES %@", "^.*[0-9]+.*$")

     let letterRegex:NSPredicate = NSPredicate(format: "SELF MATCHES %@", "^.*[A-Za-z]+.*$")

     if numberRegex.evaluate(with: string) && letterRegex.evaluate(with: string){

           print(stri)

           if allRegex.evaluate(with: string){

                print(stri)

}

}

}

isPassWord(string: "isIS112")