//------------------------------------------------------------------------------ // <copyright file="Dependency.cs" company="CNBlogs Corporation"> // Copyright (C) 2015-2016 All Rights Reserved 作 者: 请叫我头头哥 // </copyright> TestLibrary.ExtensionsClass { using System; public class AppOne { public bool Start() { Console.WriteLine(); return true; } public bool ExportLog() { Console.WriteLine(); return true; } } public class AppTwo { public bool Start() { Console.WriteLine(); return true; } public bool ExportLog() { Console.WriteLine(); return true; } } public class Monitor { public enum AppNumber { AppOne=1, AppTwo=2 } private AppOne appOne = new AppOne(); private AppTwo appTwo = new AppTwo(); private AppNumber number; public Monitor(AppNumber number) { this.number = number; } public bool StartApp() { return number == AppNumber.AppOne ? appOne.Start() : appTwo.Start(); } public bool ExportAppLog() { return number == AppNumber.AppOne ? appOne.ExportLog() : appTwo.ExportLog(); } } }

代码解析1：

在代码实现1中我们已经轻松实现了Monitor去运行已有APP并且写下LOG的需求。并且代码已经上线了.

春...夏...秋...冬...

春...夏...秋...冬...

春...夏...秋...冬...

就这样，三年过去了。

一天客户找上门了，公司业务扩展了，现在需要新加3个APP用Monitor自动化。这样我们就必须得改Monitor。

代码实现2：

//------------------------------------------------------------------------------ // <copyright file="Dependency.cs" company="CNBlogs Corporation"> // Copyright (C) 2015-2016 All Rights Reserved 作 者: 请叫我头头哥 // </copyright> TestLibrary.ExtensionsClass { using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; public class Monitor { public enum AppNumber { AppOne = 1, AppTwo = 2, AppThree = 3, AppFour = 4, AppFive = 5 } private AppOne appOne = new AppOne(); private AppTwo appTwo = new AppTwo(); private AppThree appThree = new AppThree(); private AppFour appFour = new AppFour(); private AppFive appFive = new AppFive(); private AppNumber number; public Monitor(AppNumber number) { this.number = number; } public bool StartApp() { bool result = false; if (number == AppNumber.AppOne) { result = appOne.Start(); } else if (number == AppNumber.AppTwo) { result = appTwo.Start(); } else if (number == AppNumber.AppThree) { result = appThree.Start(); } else if (number == AppNumber.AppFour) { result = appFour.Start(); } else if (number == AppNumber.AppFive) { result = appFive.Start(); } return result; } public bool ExportAppLog() { bool result = false; if (number == AppNumber.AppOne) { result = appOne.ExportLog(); } else if (number == AppNumber.AppTwo) { result = appTwo.ExportLog(); } else if (number == AppNumber.AppThree) { result = appThree.ExportLog(); } else if (number == AppNumber.AppFour) { result = appFour.ExportLog(); } else if (number == AppNumber.AppFive) { result = appFive.ExportLog(); } return result; } } }

代码解析2：