假设我有一些看起来像这样的代码:
foreach(type x in list y) { //dostuff1(x) } foreach(type x in list y) { //dostuff2(x) } foreach(type x in list y) { //dostuff3(x) } foreach(type x in list y) { //dostuff4(x) } foreach(type x in list y) { //dostuff5(x) }
我无法将事物组合成一个像这样的大循环:
foreach (type x in list y) { //dostuff1(x) //dostuff2(x) //dostuff3(x) //dostuff4(x) //dostuff5(x) }
这样做会改变顺序.有关在C#中使代码更简单的最佳方法的任何评论?
我想我可以通过创建这样的函数来解决这个问题,虽然我宁愿保持它的方式而不是强迫我的代码的未来读者理解产量:
void func(type x) { dostuff1(x) yield 0; dostuff2(x) yield 0; dostuff3(x) yield 0; dostuff4(x) yield 0; dostuff5(x) yield break; } for (int i = 0; i<5; ++i) { foreach (type x in list y) { //Call func(x) using yield semantics,which I'm not going to look up right now } }
解决方法
另一种选择:
List<Action<Foo>> actions = new List<Action<Foo>> { doStuff1,doStuff2,doStuff3,doStuff4,doStuff5 }; foreach (Action<Foo> action in actions) { foreach (Foo x in list) { action(x); } }
刚检查,这是有效的.例如:
using System; using System.Collections.Generic; public class Test { static void Main(string[] args) { var actions = new List<Action<string>> { First,Second }; foreach (var action in actions) { foreach (string arg in args) { action(arg); } } } static void First(string x) { Console.WriteLine("First: " + x); } static void Second(string x) { Console.WriteLine("Second: " + x); } }
运行Test.exe a b c的结果
First: a First: b First: c Second: a Second: b Second: c