相关疑难解决方法(0)

编辑其他选项和下面稍微扩展的问题.

考虑一个类体的这个人为的抽象例子.它演示了执行"for"迭代的四种不同方法.

private abstract class SomeClass
{
    public void someAction();
}

void Examples()
{
    List<SomeClass> someList = new List<SomeClass>();

    //A. for
    for (int i = 0; i < someList.Count(); i++)
    {
        someList[i].someAction();
    }

    //B. foreach
    foreach (SomeClass o in someList)
    {
        o.someAction();
    }

    //C. foreach extension
    someList.ForEach(o => o.someAction());

    //D. plinq
    someList.AsParallel().ForAll(o => o.someAction());

编辑:从答案和研究中添加一些选项.

    //E. ParallelEnumerable
    ParallelEnumerable.Range(0, someList.Count - 1)
        .ForAll(i => someList[i].someAction());

    //F. ForEach Parallel Extension
    Parallel.ForEach(someList, o => o.someAction());

    //G. For Parallel Extension
    Parallel.For(0, someList.Count …

我只是试图确定每个"if"语句对我的C#应用​​程序在具有大量迭代的循环中使用时的性能的影响.我没有找到关于这个的主题所以我创建了这个.

对于测试,我做了2个循环:一个没有"if",一个有一个"if"语句.代码如下.

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

namespace IfPerformance
{
    class Program
    {
        static void Main(string[] args)
        {
            int N = 500000000;
            Stopwatch sw = new Stopwatch();

            double a = 0, b = 0;
            bool f;

            sw.Restart();
            for (int i = 0; i < N; i++)
            {
                a += 1.1;
                f = a < N;
            }
            sw.Stop();
            Console.WriteLine("Without if: " + sw.ElapsedMilliseconds + " ms");

            a = 0;
            sw.Restart();
            for (int i = …