什么是考虑到事件的委托类型实例的副作用？
乔恩斯基特说，“事件不会委派的情况。” 在这里。 。 我不会问，如果我读了这个其他地方。
我一直，在过去的2个月，可视事件与事件关键字只是在防止委托的无效通过事件被调用帮助特殊类型的委托。
可能有人请详细说明如何正确可视化的整体概念的人新的C＃和基于事件的编程？
编辑1：
我的理解代表的概念，因此事件被证明是一个非常简单的概念。 我想继续和我的战斗有这些构建过程中添加由我唤出一个例子。 我加入了很多的意见更好地理解。 这意味着新的球员像我这样的：
图书馆DLL：
namespace DoSomethingLibrary
{
/*
*This is a public delegate declared at the base namespace level for global presence.
*The question is WHY do we need to have a DELEGATE here?
*The answer is: I do not want to implement the LOGGING logic. Why? Well, my consumers are many
*and all are equally demanding. They all need different types of logging. Some need HTML logging,
*some need XML logging for their custom log analyzer, some need plain text logging etc...
*This is hell for me. How am I going to support all their demands. I cannot. Thus, I ask them to
*implement LOGGING on their side. I am providing an INTERFACE(literal sense) in the guise of a DELEGATE.
*A DELEGATE is a HOOK.
*This is the hook that is needed for consumers to hook their custom loggers into the library.
*/
public delegate void Logger(string firstParam, string secondParam);
public class PrintingManiac
{
public Logger printingManiacConsumerLoggerHook;
public void StartPrintingLikeAManiac()
{
for (int iterator = 0; iterator <= 3; iterator++)
{
/*This loop is an emulator which I am using to emulate some huge processing or some huge job.
*Let us imagine that this is a library that does some heavy data crunching OR some
*extremely complex data access job etc..
*/
Console.WriteLine("Actual WORK - " + iterator.ToString());
/*After each step this library tries to LOG. But NOTE that this library
*has no LOGGER implemented. Instead, this library has judiciously DELEGATED
*the logging responsibilty to the CONSUMER of this library.
*/
printingManiacConsumerLoggerHook("Actual Work", "Step " + iterator.ToString());
}
}
}
}
对消费可执行文件：
/*
* Let us assume that I have purchased the DoSomethingLibrary DLL from a vendor.
* I have to add the DLL as a reference to my executable's project in Visual Studio.
* I also have to use the DoSomethingLibrary namespace to access the Logic in the DLL.
*/
using DoSomethingLibrary;
namespace UnderstandingDelegates
{
class Program
{
static void Main(string[] args)
{
/*
* Creating an object of the lone class PrintingManiac in the DoSomethingLibrary
*/
PrintingManiac newManiac = new PrintingManiac();
/*
* HOOKING my custom logger to the DoSomethingLibrary DLL.
* I get the best of both the worlds. I have a well-tested and efficient library working for me
* AND I have the best logging avaliable.
* The DoSomethingLibrary DLL has no knowledge of what logging this executable is going to use.
* This executable has to just satisfy the requirements of the DELEGATE signature of DoSomethingLibrary DLL.
*/
newManiac.printingManiacConsumerLoggerHook += new Logger(ClientsCustomizedLoggerTwo);
newManiac.StartPrintingLikeAManiac();
Console.ReadLine();
}
public static void ClientsCustomizedLoggerOne(string firstParam, string secondParam)
{
/*
*This logger has '=' used as a decorator
*In real scenarios the logger may be very complex.
*Let us assume this is an HTML logger
*/
Console.WriteLine("=============================");
Console.WriteLine("Delegated Logging IN CONSUMER code " + firstParam + " - " + secondParam);
Console.WriteLine("=============================");
}
public static void ClientsCustomizedLoggerTwo(string firstParam, string secondParam)
{
/*
*This logger has '-' used as a decorator
*Let us assume this is an XML logger
*/
Console.WriteLine("------------------------------");
Console.WriteLine("Delegated Logging IN CONSUMER code " + firstParam + " - " + secondParam);
Console.WriteLine("------------------------------");
}
}
}
编辑2：
我已经写了一个在CodeProject上的文章解释清楚代表的整个概念。
