tygtug@newsmth.net发文询问“能创建一个对静态类中的一组方法的访问代理吗？”
“某些类都有一组静态方法
现在想在运行时传入类名
根据类名决定执行相应的类的静态方法。
类似于指定一个类的变量似的。”
“涉及到对旧有代码的改造时的折中考虑，才会有这个需要的，不能把问题归于类的结构涉及
不合理而搪塞阿。”
偶写了一个实现Demo:
1
using System;
2
3namespace DelegateTest
4
{
5
class MainClass
6
{
7
8 [STAThread]
9 static void Main(string[] args)
10 {
11 WhoAmIDelegate d1=DelegateFactory.CreateWhoAmIDelegate("DelegateTest.ClassA");
12 WhoAmIDelegate d2=DelegateFactory.CreateWhoAmIDelegate("DelegateTest.ClassB");
13
14 Console.WriteLine(d1());
15 Console.WriteLine(d2());
16
17 long start,end;
18 int loops = 100000000;
19
20 start=DateTime.Now.Ticks;
21 for(int i=0;i<loops;i++)
22 {
23 ClassA.WhoAmI();
24
}
25 end = DateTime.Now.Ticks;
26 Console.WriteLine("{0}次直接调用ClassA.WhoAmI耗时：{1}ms",loops,(end-start)/10000);
27
28 start=DateTime.Now.Ticks;
29 for(int i=0;i<loops;i++)
30 {
31 d1();
32 }
33 end = DateTime.Now.Ticks;
34 Console.WriteLine("{0}次调用WhoAmIDelegate耗时：{1}ms",loops,(end-start)/10000);
35
36 }
37 }
38
39
40 public delegate string WhoAmIDelegate();
41
42
43 public class ClassA
44 {
45 //方法很丑陋，嘿嘿。为了性能测试方便嘛。
46 public static string WhoAmI()
47 {
48 return "ClassA";
49 }
50 }
51
52 public class ClassB
53 {
54 public static string WhoAmI()
55 {
56 return "ClassB";
57 }
58 }
59
60 public class DelegateFactory
61 {
62 public static WhoAmIDelegate CreateWhoAmIDelegate(string className)
63 {
64 return (WhoAmIDelegate)Delegate.CreateDelegate(Type.GetType("DelegateTest.WhoAmIDelegate"),Type.GetType(className),"WhoAmI");
65 }
66 }
67
}
68
using System;2
3
namespace DelegateTest4
{
5
class MainClass6
{
7
8
[STAThread]9
static void Main(string[] args)10
{11
WhoAmIDelegate d1=DelegateFactory.CreateWhoAmIDelegate("DelegateTest.ClassA");12
WhoAmIDelegate d2=DelegateFactory.CreateWhoAmIDelegate("DelegateTest.ClassB");13
14
Console.WriteLine(d1());15
Console.WriteLine(d2());16
17
long start,end;18
int loops = 100000000;19
20
start=DateTime.Now.Ticks;21
for(int i=0;i<loops;i++)22
{23
ClassA.WhoAmI();24
}25
end = DateTime.Now.Ticks;26
Console.WriteLine("{0}次直接调用ClassA.WhoAmI耗时：{1}ms",loops,(end-start)/10000);27
28
start=DateTime.Now.Ticks;29
for(int i=0;i<loops;i++)30
{31
d1();32
}33
end = DateTime.Now.Ticks;34
Console.WriteLine("{0}次调用WhoAmIDelegate耗时：{1}ms",loops,(end-start)/10000);35
36
}37
}38
39
40
public delegate string WhoAmIDelegate();41
42
43
public class ClassA44
{45
//方法很丑陋，嘿嘿。为了性能测试方便嘛。46
public static string WhoAmI()47
{48
return "ClassA";49
}50
}51
52
public class ClassB53
{54
public static string WhoAmI()55
{56
return "ClassB";57
}58
}59
60
public class DelegateFactory61
{62
public static WhoAmIDelegate CreateWhoAmIDelegate(string className)63
{64
return (WhoAmIDelegate)Delegate.CreateDelegate(Type.GetType("DelegateTest.WhoAmIDelegate"),Type.GetType(className),"WhoAmI");65
}66
}67
}68
Debug下运行结果：
ClassA
ClassB
100000000次直接调用ClassA.WhoAmI耗时：961ms
100000000次调用WhoAmIDelegate耗时：3134ms
Release下运行结果：
ClassA
ClassB
100000000次直接调用ClassA.WhoAmI耗时：210ms
100000000次调用WhoAmIDelegate耗时：2964ms