c#实现动态加载Dll(程序集)

原理如下：

1、利用反射进行动态加载和调用.
Assembly assembly=Assembly.LoadFrom(DllPath); //利用dll的路径加载,同时将此程序集所依赖的程序集加载进来,需后辍名.dll
Assembly.LoadFile 只加载指定文件，并不会自动加载依赖程序集.Assmbly.Load无需后辍名

2、加载dll后,需要使用dll中某类.
Type type=ass.GetType(“TypeName”);//用类型的命名空间和名称获得类型

3、需要实例化类型,才可以使用,参数可以人为的指定,也可以无参数,静态实例可以省略
Object obj = Activator.CreateInstance(type,params[]);//利用指定的参数实例话类型

4、调用类型中的某个方法:
需要首先得到此方法
MethodInfo mi=type.GetMethod(“MehtodName”);//通过方法名称获得方法

5、然后对方法进行调用,多态性利用参数进行控制
mi.Invoke(obj,params[]);//根据参数直线方法,返回值就是原方法的返回值

#region 声明动态载入DLL的参数
       object obj=null;
       byte[] filesByte;
        Assembly assembly;
        Type type;
        MethodInfo timerInitial;
        MethodInfo timerDispose;
        #endregion

    private void LoadDll()//加载DLL
        {
           try
            {
                filesByte = File.ReadAllBytes(Path.GetDirectoryName(Application.ExecutablePath) + "\\loadDll.dll");
                assembly = Assembly.Load(filesByte);
                type = assembly.GetType("test.loadDll");
                obj = System.Activator.CreateInstance(type);
                timerStart = tp.GetMethod("TimerStart");
                timerStop = tp.GetMethod("TimerStop");
               if (timerStart != null)
                {
                    timerStart.Invoke(obj, null);
                }
            }
           catch(Exception)
            {

            }
        }

#region 声明动态载入DLL的参数 object obj=null; byte[] filesByte; Assembly assembly; Type type; MethodInfo timerInitial; MethodInfo timerDispose; #endregion private void LoadDll()//加载DLL { try { filesByte = File.ReadAllBytes(Path.GetDirectoryName(Application.ExecutablePath) + "\\loadDll.dll"); assembly = Assembly.Load(filesByte); type = assembly.GetType("test.loadDll"); obj = System.Activator.CreateInstance(type); timerStart = tp.GetMethod("TimerStart"); timerStop = tp.GetMethod("TimerStop"); if (timerStart != null) { timerStart.Invoke(obj, null); } } catch(Exception) { } }

以下摘自MSDN

public class A
{
    public virtual int method () {return 0;}
}

public class B
{
    public virtual int method () {return 1;}
}

class Mymethodinfo
{
    public static int Main()
     {
         Console.WriteLine ("\nReflection.MethodInfo");
         A MyA = new A();
         B MyB = new B();

        // Get the Type and MethodInfo.
         Type MyTypea = Type.GetType("A");
         MethodInfo Mymethodinfoa = MyTypea.GetMethod("method");

         Type MyTypeb = Type.GetType("B");
         MethodInfo Mymethodinfob = MyTypeb.GetMethod("method");

        // Get and display the Invoke method.
         Console.Write("\nFirst method - " + MyTypea.FullName +
            " returns " + Mymethodinfoa.Invoke(MyA, null));
         Console.Write("\nSecond method - " + MyTypeb.FullName +
            " returns " + Mymethodinfob.Invoke(MyB, null));
        return 0;
     }
}