Error Handling

Try Parse

int.tryParse returns null instead of throwing when text is not a valid integer.

Program

Play the program to parse valid text, then select invalid input and watch the fallback path.

try_parse.dart 
void main() {
  var raw = ;
  var value = int.tryParse(raw);
  var label = value == null ? 'invalid' : 'value=$value';
  print(label);
}

void main() {
  var raw = ;
  var value = int.tryParse(raw);
  var label = value == null ? 'invalid' : 'value=$value';
  print(label);
}
tryParse `int.tryParse(text)` returns `int?` instead of throwing.
nullable result `value == null` checks whether parsing failed.
fallback label The ternary expression keeps output explicit for both paths.