5天玩转C#并行和多线程编程 —— 第二天 并行集合和PLinq

原文：5天玩转C#并行和多线程编程 —— 第二天 并行集合和PLinq

有修改。

using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Reflection;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApplication3
{
class Program
{
static void Main(string[] args)
{
ListWithParallel();
ConcurrentBagWithPallel();
ConcurrentBagWithPallel2();
TestPLinq();
OrderByTest();
Console.ReadLine();
}

public static void ListWithParallel()
{
Console.WriteLine("————— {0} —————", MethodBase.GetCurrentMethod().Name);
List<int> list = new List<int>();
Parallel.For(0, 10000, item =>
{
list.Add(item);
});
Console.WriteLine("List's count is {0}", list.Count());
}

public static void ConcurrentBagWithPallel()
{
Console.WriteLine("\n————— {0} —————", MethodBase.GetCurrentMethod().Name);
ConcurrentBag<int> list = new ConcurrentBag<int>();
Parallel.For(0, 10000, item =>
{
list.Add(item);
});
Console.WriteLine("ConcurrentBag's count is {0}", list.Count());
}

public static void ConcurrentBagWithPallel2()
{
Console.WriteLine("\n————— {0} —————", MethodBase.GetCurrentMethod().Name);
ConcurrentBag<int> list = new ConcurrentBag<int>();
Parallel.For(0, 10000, item =>
{
list.Add(item);
});
Console.WriteLine("ConcurrentBag's count is {0}", list.Count());
int n = 0;
foreach (int i in list)
{
if (n > 10)
break;
n++;
Console.WriteLine("Item[{0}] = {1}", n, i);
}
Console.WriteLine("ConcurrentBag's max item is {0}", list.Max());

}

public static void TestPLinq()
{
Console.WriteLine("\n————— {0} —————", MethodBase.GetCurrentMethod().Name);
Stopwatch sw = new Stopwatch();
List<Custom> customs = new List<Custom>();
for (int i = 0; i < 2000000; i++)
{
customs.Add(new Custom() { Name = "Jack", Age = 21, Address = "NewYork" });
customs.Add(new Custom() { Name = "Jime", Age = 26, Address = "China" });
customs.Add(new Custom() { Name = "Tina", Age = 29, Address = "ShangHai" });
customs.Add(new Custom() { Name = "Luo", Age = 30, Address = "Beijing" });
customs.Add(new Custom() { Name = "Wang", Age = 60, Address = "Guangdong" });
customs.Add(new Custom() { Name = "Feng", Age = 25, Address = "YunNan" });
}

sw.Start();
var result = customs.Where<Custom>(c => c.Age > 26).ToList();
sw.Stop();
Console.WriteLine("Linq time is {0}.", sw.ElapsedMilliseconds);

sw.Restart();
sw.Start();
var result2 = customs.AsParallel().Where<Custom>(c => c.Age > 26).ToList();
sw.Stop();
Console.WriteLine("Parallel Linq time is {0}.", sw.ElapsedMilliseconds);
}

public static void OrderByTest()
{
Console.WriteLine("\n————— {0} —————", MethodBase.GetCurrentMethod().Name);
Stopwatch stopWatch = new Stopwatch();
List<Custom> customs = new List<Custom>();
for (int i = 0; i < 2000000; i++)
{
customs.Add(new Custom() { Name = "Jack", Age = 21, Address = "NewYork" });
customs.Add(new Custom() { Name = "Jime", Age = 26, Address = "China" });
customs.Add(new Custom() { Name = "Tina", Age = 29, Address = "ShangHai" });
customs.Add(new Custom() { Name = "Luo", Age = 30, Address = "Beijing" });
customs.Add(new Custom() { Name = "Wang", Age = 60, Address = "Guangdong" });
customs.Add(new Custom() { Name = "Feng", Age = 25, Address = "YunNan" });
}

stopWatch.Restart();
var groupByAge = customs.GroupBy(item => item.Age).ToList();
foreach (var item in groupByAge)
{
Console.WriteLine("Age={0},count = {1}", item.Key, item.Count());
}
stopWatch.Stop();

Console.WriteLine("Linq group by time is: " + stopWatch.ElapsedMilliseconds);

stopWatch.Restart();
var lookupList = customs.ToLookup(i => i.Age);
foreach (var item in lookupList)
{
Console.WriteLine("LookUP:Age={0},count = {1}", item.Key, item.Count());
}
stopWatch.Stop();
Console.WriteLine("LookUp group by time is: " + stopWatch.ElapsedMilliseconds);
}
}

public class Custom
{
public string Name { get; set; }
public int Age { get; set; }
public string Address { get; set; }
}
}


结果：