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Java与.net的区别delegate和event

There is no delegate concept in JavaThe right-side C# program may be mimiced with reflection technology.
在Java中没有delegate的概念,而C#中delegate使用的是类似Java中反射的工具。
import java.lang.reflect.*;import java.io.*;public class Test{    public static void main(String[] args) throws Exception    {        String[] list= {"to","be","or","not","to","be"};        Method m1 = Test.class.getMethod("toConsole",new Class[] {String.class});        Display(m1, list);        Method m2 = Test.class.getMethod("toFile",new Class[] {String.class});        Display (m2, list);    }    public static void toConsole (String str)    {        System.out.print(str+" ");    }    public static void toFile (String s)    {        File f = new File("delegate.txt");        try{            PrintWriter fileOut =                new PrintWriter(new FileOutputStream(f));            fileOut.write(s);            fileOut.flush();            fileOut.close();        }catch(IOException ioe) {}    }    public static void display(Method m, String[] list)    {        for(int k = 0; k < list.length; k++) {            try {                Object[] args = {new String(list[k])};                m.invoke(null, args);            }catch(Exception e) {}        }    }} 
Delegate是引用类型允许间接访问方法。以下是简单和多维的委托Delegate
Delegates are reference types which allow indirect calls to methods. There are single and multicastdelegates.============================================ using System; using System.IO; public class DelegateTest {     public delegate void Print (String s);     public static void Main()     {         Print s = new Print (toConsole);         Print v = new Print (toFile);         Display (s);         Display (v);     }     public static void toConsole (String str)     {         Console.WriteLine(str);     }     public static void toFile (String s)     {         File f = new File("delegate.txt");         StreamWriter fileOut = f.CreateText();         fileOut.WriteLine(s);         fileOut.Flush();         fileOut.Close();     }     public static void Display(Print pMethod)     {         pMethod("This should be displayed in the console");     } }
 A delegate instance encapsulates one or more methods,  each of which is referred to as a callable entity.  To add or reduce a list of calls by using operators += or -=. for example Print p = s + v; s += v;
对比可以得出的概念是:Java中没有这个Delegate的概念,但是通过反射的方法可以实现,C#却可以通过直接使用Delegate用来实现函数方法的间接调用。