部分代码来自于网络；废话不多说，上代码：
调用方法：
object obj = WinDllInvoke("Kernel32.dll", "Beep", new object[] { 750, 300 }, typeof(void));
函数代码：
1 [System.Runtime.InteropServices.DllImport("kernel32")]
2 private static extern IntPtr LoadLibrary(string lpLibFileName);
3
4 [System.Runtime.InteropServices.DllImport("kernel32")]
5 private static extern IntPtr GetProcAddress(IntPtr hModule, string lpProcName);
6
7 [System.Runtime.InteropServices.DllImport("kernel32")]
8 private static extern IntPtr FreeLibrary(IntPtr hLibModule);
9
10 ///
11 /// 动态调用Windows DLL
12 ///
13 /// Dll文件名
14 /// 待调用的函数名
15 /// 函数参数
16 /// 返回值
17 /// 调用结果
18 private static object WinDllInvoke(string fileName, string funName, object[] objParams, Type returnType)
19 {
20 IntPtr libHandle = IntPtr.Zero;
21
22 try
23 {
24 //获取函数地址
25 libHandle = LoadLibrary(fileName);
26 if (libHandle == IntPtr.Zero) return null;
27 IntPtr procAddres = GetProcAddress(libHandle, funName);
28 if (procAddres == IntPtr.Zero) return null;
29
30 //获取参数类型
31 Type[] paramTypes = new Type[objParams.Length];
32 for (int i = 0; i < objParams.Length; ++i)
33 {
34 paramTypes[i] = objParams[i].GetType();
35 }
36
37 //构建调用方法模型
38 AssemblyName asembyName = new AssemblyName();
39 asembyName.Name = "WinDllInvoke_Assembly";
40 AssemblyBuilder asembyBuilder = AppDomain.CurrentDomain.DefineDynamicAssembly(asembyName, AssemblyBuilderAccess.Run);
41 ModuleBuilder moduleBuilder = asembyBuilder.DefineDynamicModule("WinDllInvoke");
42 MethodBuilder methodBuilder = moduleBuilder.DefineGlobalMethod("InvokeFun", MethodAttributes.Public | MethodAttributes.Static, returnType, paramTypes);
43
44 //获取一个 ILGenerator ，用于发送所需的 IL
45 ILGenerator IL = methodBuilder.GetILGenerator();
46 for (int j = 0; j < paramTypes.Length; ++j)
47 {
48 //将参数压入堆栈
49 if (paramTypes[j].IsValueType)
50 {
51 IL.Emit(OpCodes.Ldarg, j); //By Value
52 }
53 else
54 {
55 IL.Emit(OpCodes.Ldarga, j); //By Addrsss
56 }
57 }
58
59 // 判断处理器类型
60 if (IntPtr.Size == 4)
61 {
62 IL.Emit(OpCodes.Ldc_I4, procAddres.ToInt32());
63 }
64 else if (IntPtr.Size == 8)
65 {
66 IL.Emit(OpCodes.Ldc_I8, procAddres.ToInt64());
67 }
68 else
69 {
70 throw new PlatformNotSupportedException("不好意思，