[C#]『PLINQ』任务并行库使用小计

1.普通示例

using System;

using System.Collections;

using System.Collections.Generic;

using System.Diagnostics;

using System.Linq;

using System.Threading.Tasks;

namespace PLinq

{

    class Program

    {

        static IList<Person> _persons = new List<Person>();

        static void Main(string[] args)

        {

            try

            {

                CreateTextDB();

                PLINQ_Where();

            }

            catch (Exception ex)

            {

                Console.WriteLine(string.Format("Exception Message:{0}", ex.Message.Trim()));

            }

            finally

            {

                Console.ReadLine();

            }

        }

        /// <summary>

        /// 筛选

        /// </summary>

        private static void PLINQ_Where()

        {

            Stopwatch _wacth = new Stopwatch();

            _wacth.Start();

            IList<Person> _personWhereNormal = _persons.Where(p => p.Age > 10 && p.Age < 50).ToList();

            _wacth.Stop();

            Console.WriteLine(string.Format("Normal LINQ Where Cost Time:{0}", _wacth.ElapsedMilliseconds));

            _wacth.Restart();

            //WithDegreeOfParallelism

            IList<Person> _personWhereParallel = _persons.AsParallel<Person>().Where(p => p.Age > 10 && p.Age < 50).ToList();

            _wacth.Stop();

            Console.WriteLine(string.Format("PLINQ Where Cost Time:{0}", _wacth.ElapsedMilliseconds));

        }

        /// <summary>

        /// 创建测试数据

        /// </summary>

        private static void CreateTextDB()

        {

            Stopwatch _wacth = new Stopwatch();

            _wacth.Start();

            Parallel.For(0, 10000000, (i, loopstatus) =>

            {

                Person _person = new Person();

                _person.FristName = "Yan";

                _person.LastName = string.Format("Zhiwei {0}", i);

                _person.RegisterTime = DateTime.Now;

                _person.Age = i;

                lock (((ICollection)_persons).SyncRoot)

                {

                    _persons.Add(_person);

                }

            });

            _wacth.Stop();

            Console.WriteLine(string.Format("Create TextDB Cost Time:{0},Count:{1}", _wacth.ElapsedMilliseconds, _persons.Count));

        }

    }

    class Person

    {

        public string FristName { get; set; }

        public string LastName { get; set; }

        public int Age { get; set; }

        public DateTime RegisterTime { get; set; }

    }

}

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }代码效果

 

2.异常处理

using System;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Threading.Tasks;

namespace PLinq
{
    class Program
    {
        static IList<Person> _persons = new List<Person>();
        static void Main(string[] args)
        {
            try
            {
                CreateTextDB();
                PINQ_Exception();
            }
            catch (Exception ex)
            {
                Console.WriteLine(string.Format("Exception Message:{0}", ex.Message.Trim()));
            }
            finally
            {
                Console.ReadLine();
            }
        }
        private static void PINQ_Exception()
        {
            /*
             * 这样处理，当出现异常的时候不会影响下次foralll遍历
             */
            Func<int, bool> isTure = (age) =>
            {
                try
                {
                    if (age > 1989222)
                        throw new Exception("PLINQ Text");
                    Console.WriteLine(age);
                    return true;
                }
                catch (Exception ex)
                {
                    Console.WriteLine(ex.Message);
                    return false;
                }
            };
            _persons.AsParallel<Person>().ForAll(p => isTure(p.Age));

        }
        /// <summary>
        /// 创建测试数据
        /// </summary>
        private static void CreateTextDB()
        {
            Stopwatch _wacth = new Stopwatch();
            _wacth.Start();
            Parallel.For(0, 10000000, (i, loopstatus) =>
            {
                Person _person = new Person();
                _person.FristName = "Yan";
                _person.LastName = string.Format("Zhiwei {0}", i);
                _person.RegisterTime = DateTime.Now;
                _person.Age = i;
                lock (((ICollection)_persons).SyncRoot)
                {
                    _persons.Add(_person);
                }
            });
            _wacth.Stop();
            Console.WriteLine(string.Format("Create TextDB Cost Time:{0},Count:{1}", _wacth.ElapsedMilliseconds, _persons.Count));
        }
    }
    class Person
    {
        public string FristName { get; set; }
        public string LastName { get; set; }
        public int Age { get; set; }
        public DateTime RegisterTime { get; set; }
    }
}

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }

代码效果

 

3.取消 PLINQ 查询

using System;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;

namespace PLinq
{
    class Program
    {
        static IList<Person> _persons = new List<Person>();
        static void Main(string[] args)
        {
            try
            {
                CreateTextDB();
                PINQ_Cancellation();
            }
            catch (Exception ex)
            {
                Console.WriteLine(string.Format("Exception Message:{0}", ex.Message.Trim()));
            }
            finally
            {
                Console.ReadLine();
            }
        }
        private static void PINQ_Cancellation()
        {
            try
            {
                /*
                 * 当您在用户代码中处理取消时，不必在查询定义中使用 WithCancellation<TSource>。 但是，我们建议您这样做，原因是 WithCancellation<TSource> 对查询性能没有影响，
                 * 并且它使取消能够由查询运算符和用户代码进行处理。 为了确保系统响应能力，我们建议您大约每毫秒检查是否存在取消一次；
                 * 不过，任何 10 毫秒以下的期间都被视为可接受。 此频率对代码的性能应没有负面影响。 ——MSDN
                 */
                CancellationTokenSource _cancel = new CancellationTokenSource();
                Func<int, bool> isTure = (age) =>
                {
                    if (age > 1989222)
                        _cancel.Cancel();
                    Console.WriteLine(age);
                    return true;
                };
                _persons.AsParallel<Person>().WithCancellation(_cancel.Token).ForAll(p => isTure(p.Age));
            }
            catch (OperationCanceledException ex)
            {
                Console.WriteLine(string.Format("OperationCanceledException Message:{0}", ex.Message));
            }
        }
        /// <summary>
        /// 创建测试数据
        /// </summary>
        private static void CreateTextDB()
        {
            Stopwatch _wacth = new Stopwatch();
            _wacth.Start();
            Parallel.For(0, 10000000, (i, loopstatus) =>
            {
                Person _person = new Person();
                _person.FristName = "Yan";
                _person.LastName = string.Format("Zhiwei {0}", i);
                _person.RegisterTime = DateTime.Now;
                _person.Age = i;
                lock (((ICollection)_persons).SyncRoot)
                {
                    _persons.Add(_person);
                }
            });
            _wacth.Stop();
            Console.WriteLine(string.Format("Create TextDB Cost Time:{0},Count:{1}", _wacth.ElapsedMilliseconds, _persons.Count));
        }
    }
    class Person
    {
        public string FristName { get; set; }
        public string LastName { get; set; }
        public int Age { get; set; }
        public DateTime RegisterTime { get; set; }
    }
}

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }

代码效果