Unity C# for和foreach效率比较

先说测试结果：效率几乎完全一样，不用特意改变写法，喜欢哪种用哪种。测试代码：using UnityEngine;using UnityEditor;using System.Diagnostics;/// <summary>/// 执行时间测试/// ZhangYu 2019-04-13/// </summary>public class TimeTest : MonoBehaviour { private static Stopwatch watch; private void Start() { Execute(); } [MenuItem(“CONTEXT/TimeTest/执行”)] private static void Execute() { watch = new Stopwatch(); // 数据长度 int total = 100000000; int[] array = new int[total]; for (int i = 0; i < total; i++) { array[i] = i + 1; } // Foreach watch.Reset(); watch.Start(); foreachTest(array); watch.Stop(); string msgForeach = string.Format(“Foreach: {0}s”, watch.Elapsed); // For1 watch.Reset(); watch.Start(); foreachTest(array); watch.Stop(); string msgFor1 = string.Format(“For1: {0}s”, watch.Elapsed); // For2 watch.Reset(); watch.Start(); foreachTest(array); watch.Stop(); string msgFor2 = string.Format(“For2: {0}s”, watch.Elapsed); print(msgForeach); print(msgFor1); print(msgFor2); } // (1)0.7035506s // (2)0.7174406s // (3)0.7001000s // (4)0.7012998s // (5)0.7009337s public static void foreachTest(int[] array) { foreach (int item in array) { } } // (1)0.7014426s // (2)0.7172180s // (3)0.6987379s // (4)0.6987784s // (5)0.7051741s public static void forTest1(int[] array) { for (int i = 0; i < array.Length; i++) { } } // (1)0.7006860s // (2)0.7160505s // (3)0.6997564s // (4)0.7024032s // (5)0.7004985s public static void forTest2(int[] array) { int length = array.Length; for (int i = 0; i < length; i++) { } }}测试结果：排除运行环境的误差，for循环和foreach循环在数十次的测试结果中，效率基本是完全一样的，For2方法优化了一下length的取值，但没什么明显的性能差距，所以for和foreach喜欢那种用哪种吧，不用为了提高效率特意改变写法或习惯。