C＃Linq-獲取包含整數列表的所有元素

Question

我有一個對象列表，每個對象內部都有類型列表，類似這樣的東西：

public class ExampleObject
{
    public int Id {get; set;}
    public IEnumerable <int> Types {get;set;}
}

例如：

var typesAdmited = new List<int> { 13, 11, 67, 226, 82, 1, 66 };

在對象列表中，我有一個像這樣的對象：

Object.Id = 288;
Object.Types = new List<int> { 94, 13, 11, 67, 254, 256, 226, 82, 1, 66, 497, 21};

但是，當我使用linq來獲取所有具有允許的類型的Object時，我會得到任何結果。 我正在嘗試：

var objectsAdmited = objects.Where(b => b.Types.All(t => typesAdmited.Contains(t)));

例：

var typesAdmited = new List<int> { 13, 11, 67, 226, 82, 1, 66 };

var objectNotAdmited = new ExampleObeject {Id = 1, Types = new List<int> {13,11}}; 
var objectAdmited = new ExampleObject {Id = 288, Types = new List<int> { 94, 13, 11, 67, 254, 256, 226, 82, 1, 66, 497, 21}};

var allObjects = new List<ExampleObject> { objectNotAdmited, objectAdmited };

var objectsAdmited = allObjects.Where(b => b.Types.All(t => typesAdmited.Contains(t)));

我得到：

objectsAdmited = { }

它應該是：

objectsAdmited = { objectAdmited }

Answer 1

您必須交替更改LINQ查詢中的兩個列表：

var objectsAdmited = allObjects.Where(b => typesAdmited.All(t => b.Types.Contains(t)));

Answer 2

您可以使用Linq解決此問題。 看到中間的小代碼塊-其余的部分使它成為最小的完整驗證模板 ：

using System;
using System.Collections.Generic;
using System.Linq; 

public class ExampleObject
{
  public int Id { get; set; }
  public IEnumerable<int> Types { get; set; }
}

class Program
{
  static void Main (string [] args)
  {
    var obs = new List<ExampleObject>
    {
      new ExampleObject
      {
        Id=1,
        Types=new List<int> { 94, 13, 11, 67, 254, 256, 226, 82, 1, 66, 497, 21 } 
      },
      new ExampleObject
      {
        Id=288,
        Types=new List<int> { 94, 13, 11, 67,      256, 226, 82, 1, 66, 497, 21 } 
      },
    };

    var must_support = new List<int>{11, 67, 254, 256, 226, 82, };  // only Id 1 fits

    var must_support2 = new List<int>{11, 67, 256, 226, 82, };      // both fit

    // this is the actual check: see for all objects in obs 
    // if all values of must_support are in the Types - Listing
    var supports  = obs.Where(o => must_support.All(i => o.Types.Contains(i)));
    var supports2 = obs.Where(o => must_support2.All(i => o.Types.Contains(i)));

    Console.WriteLine ("new List<int>{11, 67, 254, 256, 226, 82, };");
    foreach (var o in supports)
      Console.WriteLine (o.Id);

    Console.WriteLine ("new List<int>{11, 67, 256, 226, 82, };");
    foreach (var o in supports2)
      Console.WriteLine (o.Id);

    Console.ReadLine ();
  }
}

輸出：

new List<int>{11, 67, 254, 256, 226, 82, };
1
new List<int>{11, 67, 256, 226, 82, };
1
288