从颤动的其他对象列表中删除对象列表

Question

我想获得 availableSlots = allSlots-bookedSlots，这是代码，请帮忙！

final List<timeSlot> allSlots=
[
TimeSlot(time: '6PM-7PM', isSelected: false),
TimeSlot(time: '7PM-8PM', isSelected: false),
TimeSlot(time: '8PM-9PM', isSelected: false),
];
final List<timeSlot> bookedSlots=
[
TimeSlot(time: '6PM-7PM', isSelected: false),
TimeSlot(time: '7PM-8PM', isSelected: false),
];

这是 TimeSlot 类

  class TimeSlot {
  String time;
  bool isSelected;

  TimeSlot({this.isSelected, this.time});
}

Answer 1

首先覆盖“==”运算符以比较两个 TimeSlot 值。

并从 allSlots 中过滤 bookingSlots 项目以获取 availableSlots。

void main() {
  final List<TimeSlot> allSlots=
  [
    TimeSlot(time: '6PM-7PM', isSelected: false),
    TimeSlot(time: '7PM-8PM', isSelected: false),
    TimeSlot(time: '8PM-9PM', isSelected: false),
  ];
  final List<TimeSlot> bookedSlots=
  [
    TimeSlot(time: '6PM-7PM', isSelected: false),
    TimeSlot(time: '7PM-8PM', isSelected: false),
  ];
  
  
  List<TimeSlot> availableSlots = allSlots.where((item) => !bookedSlots.contains(item)).toList();
  print(allSlots);
  print(availableSlots);
}

 class TimeSlot {
  String? time;
  bool? isSelected;

  TimeSlot({this.isSelected, this.time});
   
  @override
  bool operator==(Object other) {
    return other is TimeSlot && other.time == time &&other.isSelected == isSelected;
  }
   
   
   @override
  String toString() => '''TimeSlot {
     time: $time,
     isSelected: $isSelected,
  }''';
   

   @override
   int get hashCode => Object.hash(time, isSelected);
   
}

Answer 2

如果您想测试，请将以下代码复制到 dartpad 中：https://dartpad.dev/

void main() {
  
  
  List<SomeClass> list1 = [SomeClass('item 1'), SomeClass('item 2'), SomeClass('item 3')];
  List<SomeClass> list2 = [SomeClass('item 1'), SomeClass('item 3')];
  

  List<SomeClass> deltaList = [];
   
  print(list1);
  
  deltaList = list1;
  
  print(deltaList);
  
  for(SomeClass item in list2){
   
    deltaList.removeWhere((delta) => delta.name == item.name);
      
  }
  
  for (SomeClass item in deltaList){
    print(item.name);
  }
  
 
}


class SomeClass{
  String name;
  SomeClass(this.name);
}