dart_exceptions.dart

dart_exceptions.dart

import 'dart:math' as math;

class MyError extends Error {}

class MyException implements Exception {
  MyException([dynamic message]);
}

void checkValue(int value) {
  switch(value) {
    case 1: 
      throw FormatException('Expected at least 1 section');
    case 2:
      throw 'Expected at least 1 section';
    case 3:
      throw MyError();
    case 4: 
      throw MyException();
  }
  
}


void main() {
  final value = math.Random().nextInt(10);
  try {
    checkValue(value);
    print('no exceptions');
  } on MyError {
    print('MyError');
  } on MyException catch (e) {
    print('MyException: $e');
  } on FormatException catch (e) {
    print('FormatException: $e');
  } catch (e, s) {
    print('print error ${e.runtimeType} $s'); // print error with StackTrace
    rethrow; // Allow callers to see the exception.
  } finally {
    print('End!');
  }
}