实现代码
1 using System;
2 using System.Collections.Generic;
3 using System.Linq;
4 using System.Text;
5 using System.Threading.Tasks;
6 using System.Threading;
7 using System.Collections.Concurrent;
8
9 namespace CSharpStudy.ParallelStudy
10 {
11 class HowToReturnList
12 {
13 public static void Error_Test()
14 {
15 var list = Enumerable.Range(1, 1000);
16
17 var results = new List<string>();
18 Parallel.ForEach(list, (item) =>
19 {
20 results.Add("item:" + item);
21 });
22
23 Console.WriteLine(results.Count);
24 }
25
26 public static void Lock_Test()
27 {
28 var list = Enumerable.Range(1, 1000);
29
30 var results = new List<string>();
31 Parallel.ForEach(list, (item) =>
32 {
33 lock (results)
34 {
35 results.Add("item:" + item);
36 }
37 });
38
39 Console.WriteLine(results.Count);
40 }
41
42 public static void Concurrent_Collections_Test()
43 {
44 var list = Enumerable.Range(1, 1000);
45
46 var results = new ConcurrentQueue<string>();
47 Parallel.ForEach(list, (item) =>
48 {
49 lock (results)
50 {
51 results.Enqueue("item:" + item);
52 }
53 });
54
55 Console.WriteLine(results.Count);
56 }
57
58 public static void Task_Test()
59 {
60 var list = Enumerable.Range(1, 1000);
61
62 var tasks = list.Select(item =>
63 {
64 return Task.Run<string>(() =>
65 {
66 return "item:" + item;
67 });
68 }).ToArray();
69 Task.WhenAll(tasks);
70
71 Console.WriteLine(tasks.Select(x => x.Result).Count());
72 }
73
74 public static void PLinq_Test()
75 {
76 var list = Enumerable.Range(1, 1000);
77
78 var results = list.AsParallel().Select(item => "item:" + item);
79
80 Console.WriteLine(results.Count());
81 }
82 }
83 }
