Question

我正在尝试过滤掉ObservableCollection<MainBusinessObject>，我需要过滤集合中Subobject.PropertyX == true的所有项目。

  MainBusinessObject 
     - PropertyA int
     - PropertyB string
     - ListOfSubobject ObservableCollection<Subobject>

  Subobject
     - PropertyX bool
     - PropertyY int
     - PropertyZ - string

我真的想远离循环和if语句，但我似乎无法正确获取LinQ语句。这就是我到目前为止所做的：

return (MainBusinessObjectCollection) 
          listOfMainBusinessObject.Where(x =>
           (x as MainBusinessObject).CanBePartitioned == true);

修改我需要从主要业务对象

中过滤掉ListOfSubobject

Answer 1

取决于您是否希望任何子对象具有该属性或所有子对象具有该属性：

var filteredList = listOfMainBusinessObject
                       .Where(x => x.ListOfSubobject.Any(s=>s.PropertyX));

或

var filteredList = listOfMainBusinessObject
                      .Where(x => x.ListOfSubobject.All(s=>s.PropertyX));

你也有一些看似无效或不必要的演员表。要转换为MainBusinessObjectCollection（假设它是MainBusinessObject s的集合），您可能必须从IEnumerable返回Where来初始化它：< / p>

var newList = new MainBusinessObjectCollection(filteredList);

Answer 2

如果您希望所有Subobjects与Subobject.PropertyX == true：

listOfMainBusinessObject.SelectMany(x => x.ListOfSubobject)
                        .Where(x => x.PropertyX == true);

LinQ过滤声明

2 个答案: