How to catch exception in flutter?

Question

This is my exception class. Exception class has been implemented by the abstract exception class of flutter. Am I missing something?

class FetchDataException          


        

Answer 1

To handle errors in an async and await function, use try-catch:

Run the following example to see how to handle an error from an asynchronous function.

Future printOrderMessage() async {
  try {
    var order = await fetchUserOrder();
    print('Awaiting user order...');
    print(order);
  } catch (err) {
    print('Caught error: $err');
  }
}

Future fetchUserOrder() {
  // Imagine that this function is more complex.
  var str = Future.delayed(
      Duration(seconds: 4),
      () => throw 'Cannot locate user order');
  return str;
}

Future main() async {
  await printOrderMessage();
}

Within an async function, you can write try-catch clauses the same way you would in synchronous code.