最新下载
热门教程
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
Delegates in C# - an introduction(转:英文)
时间:2022-07-02 18:03:21 编辑:袖梨 来源:一聚教程网
Introduction
I assume that most people who want to learn C# are C/C++ programmers. Thus I believe that they will be looking for features in C# which are analogous to some C/C++ feature they were quite fond of. And one of my favorite features about good old C was function pointers. Those of you who haven't used function pointers missed out on the fun. Well C# does have something that can be used where we used to use function pointers. Actually they do a lot more than function pointers used to do. They are called delegates. As is usual with me, I'll try and demonstrate the use of delegates through commented, sample programs that are small, simple and hopefully easy to understand.
Program 1
In this program we'll see how delegates are used to encapsulate a reference to a method in a delegate object. As you can see we can declare delegates in a namespace and thus delegates are shareable among classes. You can also see that we can associate a delegate variable with both static and instance member functions.
using System;
//declare our delegate type
public delegate void dgate();
class nish
{
public static void Main()
{
test t1 = new test();
//create a new delegate object and associate it
//with the function abc in class test
dgate d1 = new dgate(t1.abc);
d1(); //call the delegate
//now associate the delegate object with
//the function xyz in class test
d1 = new dgate(t1.xyz);
d1(); //call the delegate
I assume that most people who want to learn C# are C/C++ programmers. Thus I believe that they will be looking for features in C# which are analogous to some C/C++ feature they were quite fond of. And one of my favorite features about good old C was function pointers. Those of you who haven't used function pointers missed out on the fun. Well C# does have something that can be used where we used to use function pointers. Actually they do a lot more than function pointers used to do. They are called delegates. As is usual with me, I'll try and demonstrate the use of delegates through commented, sample programs that are small, simple and hopefully easy to understand.
Program 1
In this program we'll see how delegates are used to encapsulate a reference to a method in a delegate object. As you can see we can declare delegates in a namespace and thus delegates are shareable among classes. You can also see that we can associate a delegate variable with both static and instance member functions.
using System;
//declare our delegate type
public delegate void dgate();
class nish
{
public static void Main()
{
test t1 = new test();
//create a new delegate object and associate it
//with the function abc in class test
dgate d1 = new dgate(t1.abc);
d1(); //call the delegate
//now associate the delegate object with
//the function xyz in class test
d1 = new dgate(t1.xyz);
d1(); //call the delegate
相关文章
- 《夜族崛起》铁匠西里尔位置一览 05-17
- 《寓言之地》1.02更新内容一览 05-17
- 《辐射4》steam好评率介绍 05-17
- 《夜族崛起》技能强化珠宝掉落说明 05-17
- 《辐射4》主机控制台介绍 05-17
- 《星露谷物语》海草和绿藻获取方法 05-17