C# Linq - 如何从仅包含另一个列表项目的列表中选择项目？
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Linq - How to select items from a list that contains only items of another list?
提问by Gypsy
I have this two classes:
我有这两个类：
public class Item
{
public int Id{get;set;}
public List<Test> TestList{get;set;}
}
public class Test
{
public int Id{get;set;}
public Item Item{get;set;}
public byte State{get;set;}
}
Item Class Data:
项目类别数据：
Id
1
2
3
And Test Class Data:
和测试类数据：
Item State
1 1
1 2
1 3
2 1
2 4
3 2
Now i need to write a query that select the Items from my class that just have state of 1 and 2.For example for the sample above it should returns row with Item=3. i wrote this query:
现在我需要编写一个查询，从我的类中选择状态为 1 和 2 的项目。例如，对于上面的示例，它应该返回带有 Item=3 的行。我写了这个查询：
var stateList=new List<byte>(){1,2};
Items.Where(x => x.TestList.Select(c => c.State).Any(s => stateList.Contains(s)));
but it returns Item=1 either.Any Idea?
但它也返回 Item=1。有什么想法吗？
采纳答案by Ahmed KRAIEM
This returns the items which all states are in stateList, I think that that's what you need:
这将返回所有状态所在的项目stateList，我认为这就是您所需要的：
Items.Where(x => x.TestList.All(s => stateList.Contains(s.State)));
回答by Yaugen Vlasau
in case you need only those items which TestList have only items with status 2:
如果您只需要 TestList 只有状态为 2 的项目的那些项目：
tems.Where( i => i.TestList.All(li => li.State == 2))
