Dart： Use... In a loop Async and Await

stay Dart（ as well as Flutter） in , You can use Future.forEach Perform synchronization operations sequentially in the loop . The following example program will print from 1 To 10 The number of . Print one number at a time , It will wait 3 second , Then print the next number .

// Big front end tour 
void main() async {
  final items = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
  await Future.forEach(items, (item) async {
    print(item);
    await Future.delayed(const Duration(seconds: 3));
  });
}

Another way is to use... In grammar for … , As shown below ：

//  Big front end tour 
void main() async {
  final items = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
  for (int item in items) {
    print(item);
    await Future.delayed(const Duration(seconds: 3));
  }
}