1. // String -> int
    2. var one = int.parse('1');
    3. assert(one == 1);
    5. // String -> double
    6. var onePointOne = double.parse('1.1');
    7. assert(onePointOne == 1.1);
    9. // int -> String
    10. String oneAsString = 1.toString();
    11. assert(oneAsString == '1');
    13. // double -> String
    14. String piAsString = 3.14159.toStringAsFixed(2);
    15. assert(piAsString == '3.14');