13518219792
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Collections.Concurrent;
using System.Threading;
using System.Diagnostics;
namespace ConsoleApplication5
{
class Program
{
static void Main(string[] args)
{
//并行LINQ
//******************************************************
//测试时间
Stopwatch sw = Stopwatch.StartNew();
long l = sw.ElapsedMilliseconds;
//******************************************************
const int maxsize = 100000000;
var data = new int[maxsize];
Random ran = new Random();
for (int i = 0; i < maxsize; i++)
{
checked
{
data[i] = ran.Next(40);
}
}
//===========================================并行查询
//AsParallel() 启用查询的并行化
//AsParallel() 返回ParallelQuery,所以Where()、Select()等方法不在返回IEnumerable，而返回ParallelQuery
var query = (from r in data.AsParallel()
select r).Take(20).Select(r => r);
Foreach(query);
Console.WriteLine(data.AsParallel().Where(r => r < 20).Sum());
//===========================================分区器
List il = Enumerable.Range(0, 10000).ToList();
//WithExecutionMode(ParallelExecutionMode.ForceParallelism) //强制并行化整个查询
//WithDegreeOfParallelism() //指定最大任务数
var query2 = (from r in Partitioner.Create(il, true).AsParallel().WithExecutionMode(ParallelExecutionMode.ForceParallelism)
where r < 20
select r).Sum();
Console.WriteLine("====================================");
Console.WriteLine(query2);
Console.WriteLine("====================================");
//===========================================取消长时间运行的任务
var token = new CancellationTokenSource();
new Thread(() =>
{
try
{
var query3 = (from r in il.AsParallel().WithCancellation(token.Token)
where r < 20
select r
).Sum();
Console.WriteLine(query3);
}
catch (Exception e) { Console.WriteLine(e); }
}).Start();
if (Console.ReadLine() == "y" || Console.ReadLine() == "Y")
{
token.Cancel();
}
Console.ReadKey();
}
public static void Foreach(IEnumerable s)
{
Console.WriteLine("==================================");
foreach (var item in s)
{
Console.WriteLine(item);
}
}
}
}
