C#避免过长的IF和Switch分支的方法

C#避免过长的IF和Switch分支的方法

1.最蠢形态

//很丑有没有！
//这个分支要是一两个还是可以接受的
class Program
{
static void Main(string[] args)
{
Command("播放");
Console.ReadKey();
}

public static void Command(String _command)
{
switch(_command)
{
case "播放":
Console.WriteLine("开始"+_command+"了！！");
break;
case "快进":
Console.WriteLine("开始" + _command + "了！！");
break;
case "暂停":
Console.WriteLine("开始" + _command + "了！！");
break;
case "结束":
Console.WriteLine("开始" + _command + "了！！");
break;
}
}
}

2.表驱动形态

//这个表驱动 还可以利用反射去做
//这个比上面的强多了有没有？
class Program
{

public static Dictionary<string, Action> dic;

static void Main(string[] args)
{
dic = new Dictionary<string, Action> {
{"播放", () => { Console.WriteLine("开始播放了！！"); }},
{"快进", () => { Console.WriteLine("开始快进了！！"); }},
{"暂停", () => { Console.WriteLine("开始暂停了！！");}}
};
//可以动态的添加命令和方法
dic.Add("结束", () => { Console.WriteLine("开始结束了！！"); });
Command(dic, "播放");
Command(dic, "快进");
Command(dic, "结束");
Command(dic, "快进两倍");

Console.ReadKey();

}

static void Command(Dictionary<string, Action> _dic,String _command)
{
if (_dic.ContainsKey(_command))
{
_dic_command;
}
else
{
Console.WriteLine("没有命令啊！！");
}
}
}

3.多态形态

//利用多态来处理
//好处就是再添加命令时候不用修改，直接添加命令类就可以了
class Program
{
static void Main(string[] args)
{
Commander _commander = new PlayCommander();
_commander.Execute();

_commander = new FinishCommander();
_commander.Execute();

_commander = new SpeedCommander();
_commander.Execute();

Console.ReadKey();
}
}

abstract class Commander
{
public abstract void Execute();
}

class PlayCommander : Commander
{
public override void Execute()
{
Console.WriteLine("开始播放了了！！");
}
}

class SpeedCommander : Commander
{
public override void Execute()
{
Console.WriteLine("开始快进了了！！");
}
}

class PauseCommander : Commander
{
public override void Execute()
{
Console.WriteLine("开始暂停了了！！");
}
}

class FinishCommander : Commander
{
public override void Execute()
{
Console.WriteLine("开始结束了了！！");
}
}