C#网络编程一：C#网络编程常用特性
引用：https://www.cnblogs.com/dotnet261010/p/6206068.html
特性一：委托
委托是C#语言中特有的概念，相当于C/C++中的函数指针，与C/C++中函数指针的不同之处是：委托是面向对象的、类型安全的和保险的，是引用类型。因此，对委托的使用要
“先定义、后声明，接着实例化、然后作为参数传递给方法，最后才能使用”。
1、定义委托使用关键字delegate:
delegate void SomeDelegate(type1 para1,......typen paran);
2、声明委托：
SomeDelegate d;
3、实例化委托：
d=new SomeDelegate(obj.InstanceMethod);
其中obj是对象，InstanceMethod是它的实例方法。
4、作为参数传递给方法
someMethod(d);
5、最后在此方法的实现代码中使用委托
private void someMethod(SomeDelegate someDelegate)
{
.....
//使用委托
someDelegate(arg1,arg2,....,argn);
......
}
通过委托SomeDelegate实现对方法InstanceMethod的调用，调用还必须有一个前提条件：方法InstanceMethod有参数且和定义SomeDelegate的参数一致，并且返回类型相同（本例中为void）。方法InstanceMethod的定义：
private void InstanceMethod(type1 para1,type2 para2,......,typen paran)
{
//方法体
.....
}
委托的实例化中的参数既可以是实例方法，也可以是静态方法。
使用委托实现“文字抄写员”的小程序，界面如下：
在下方文本框中编辑文字，勾选“书写到”组框中的“文本区1”和（或）“文本区2”复选框后单击“提交”按钮，程序会自动将文本框中的文字“抄写”到对应的用户勾选的文本区中去。
代码实现如下：
1 using System;
2 using System.Collections.Generic;
3 using System.ComponentModel;
4 using System.Data;
5 using System.Drawing;
6 using System.Linq;
7 using System.Text;
8 using System.Threading.Tasks;
9 using System.Windows.Forms;
10
11 namespace DelegateDemo
12 {
13 public partial class FrmMain : Form
14 {
15 public FrmMain()
16 {
17 InitializeComponent();
18 }
19
20 //1、定义委托
21 private delegate void WriteToTextBox(string strTxt);
22 //2、声明委托
23 private WriteToTextBox writeToTextBox;
24
25 /// <summary>
26 /// 提交
27 /// </summary>
28 /// <param name="sender"></param>
29 /// <param name="e"></param>
30 private void btn_OK_Click(object sender, EventArgs e)
31 {
32 if (chbOne.Checked)
33 {
34 gbJobOne.Text = "运行中......";
35 gbJobOne.Refresh();
36 txtJobOne.Clear();
37 //3、实例化委托
38 writeToTextBox = new WriteToTextBox(WriteTextBox1);
39 //4、将委托作为方法的参数进行传递
40 WriteText(writeToTextBox);
41 gbJobOne.Text = "任务1完成";
42 }
43 if (chbTwo.Checked)
44 {
45
46 gbJobTwo.Text = "运行中......";
47 gbJobTwo.Refresh();
48 txtJobTwo.Clear();
49 //3、实例化委托
50 writeToTextBox = new WriteToTextBox(WriteTextBox2);
51 //4、将委托作为方法的参数进行传递
52 WriteText(writeToTextBox);
53 gbJobTwo.Text = "任务2完成";
54 }
55 }
56
57
58 private void WriteText(WriteToTextBox writeMethod)
59 {
60 string strData = this.txt_Input.Text;
61 writeMethod(strData);
62 }
63 private void WriteTextBox1(string strTxt)
64 {
65 this.txtJobOne.Text = strTxt;
66 }
67
68 private void WriteTextBox2(string strTxt)
69 {
70 this.txtJobTwo.Text = strTxt;
71 }
72
73 /// <summary>
74 /// 窗体加载事件
75 /// </summary>
76 /// <param name="sender"></param>
77 /// <param name="e"></param>
78 private void FrmMain_Load(object sender, EventArgs e)
79 {
80 //设置文本框获取焦点
81 this.ActiveControl = this.txt_Input;
82 //this.txt_Input.Focus();
83 }
84 }
85 }
特性2：多线程
多线程的具体介绍请参考博文：http://www.cnblogs.com/dotnet261010/p/6159984.html
使用多线程实现上一节的程序，代码如下：
1 using System;
2 using System.Collections.Generic;
3 using System.ComponentModel;
4 using System.Data;
5 using System.Drawing;
6 using System.Linq;
7 using System.Text;
8 using System.Threading.Tasks;
9 using System.Windows.Forms;
10 using System.Threading;//引入多线程的命名空间
11
12 namespace DelegateDemo
13 {
14 public partial class FrmMain : Form
15 {
16 public FrmMain()
17 {
18 InitializeComponent();
19 }
20
21 //1、定义委托
22 private delegate void WriteToTextBox(string strTxt);
23 //2、声明委托
24 private WriteToTextBox writeToTextBox;
25
26 /// <summary>
27 /// 提交
28 /// </summary>
29 /// <param name="sender"></param>
30 /// <param name="e"></param>
31 private void btn_OK_Click(object sender, EventArgs e)
32 {
33 //创建线程1
34 Thread thread1 = new Thread(new ThreadStart(ExecuteTsk1));
35 //启动线程1
36 thread1.Start();
37
38 //创建线程2
39 Thread thread2 = new Thread(new ThreadStart(ExecuteTsk2));
40 //启动线程2
41 thread2.Start();
42
43 }
44
45
46 private void ExecuteTsk1()
47 {
48 if (chbOne.Checked)
49 {
50 gbJobOne.Text = "运行中......";
51 gbJobOne.Refresh();
52 txtJobOne.Clear();
53 //3、实例化委托
54 writeToTextBox = new WriteToTextBox(WriteTextBox1);
55 //4、将委托作为方法的参数进行传递
56 WriteText(writeToTextBox);
57 gbJobOne.Text = "任务1完成";
58 }
59 }
60
61 private void ExecuteTsk2()
62 {
63 if (chbTwo.Checked)
64 {
65
66 gbJobTwo.Text = "运行中......";
67 gbJobTwo.Refresh();
68 txtJobTwo.Clear();
69 //3、实例化委托
70 writeToTextBox = new WriteToTextBox(WriteTextBox2);
71 //4、将委托作为方法的参数进行传递
72 WriteText(writeToTextBox);
73 gbJobTwo.Text = "任务2完成";
74 }
75 }
76
77
78 private void WriteText(WriteToTextBox writeMethod)
79 {
80 string strData = this.txt_Input.Text;
81 writeMethod(strData);
82 }
83 private void WriteTextBox1(string strTxt)
84 {
85 this.txtJobOne.Text = strTxt;
86 }
87
88 private void WriteTextBox2(string strTxt)
89 {
90 this.txtJobTwo.Text = strTxt;
91 }
92
93 /// <summary>
94 /// 窗体加载事件
95 /// </summary>
96 /// <param name="sender"></param>
97 /// <param name="e"></param>
98 private void FrmMain_Load(object sender, EventArgs e)
99 {
100 //设置文本框获取焦点
101 this.ActiveControl = this.txt_Input;
102 //允许跨线程调用
103 Control.CheckForIllegalCrossThreadCalls = false;
104 }
105 }
106 }
特性3：C#方法回调
C#回调的具体介绍请参照博文：http://www.cnblogs.com/dotnet261010/p/6159984.html
使用委托、多线程和C#的方法回调机制实现上一节的程序，代码如下：
1 using System;
2 using System.Collections.Generic;
3 using System.ComponentModel;
4 using System.Data;
5 using System.Drawing;
6 using System.Linq;
7 using System.Text;
8 using System.Threading.Tasks;
9 using System.Windows.Forms;
10 using System.Threading;//引入多线程的命名空间
11
12 namespace DelegateDemo
13 {
14 public partial class FrmMain : Form
15 {
16 public FrmMain()
17 {
18 InitializeComponent();
19 }
20
21 //1、定义委托
22 private delegate void WriteToTextBox(string strTxt);
23 //2、声明委托
24 private WriteToTextBox writeToTextBox;
25
26 //定义并声明操作文本区1的回调
27 private delegate void WriteTxtJobOneCallBack(string strValue);
28 WriteTxtJobOneCallBack writeTxtJobOneCallBack;
29
30 //定义并声明操作文本区2的回调
31 private delegate void WriteTxtJobTwoCallBack(string strValue);
32 WriteTxtJobOneCallBack writeTxtJobTwoCallBack;
33
34 //定义并声明操作"任务1"分组框的回调
35 private delegate void ShowGroupOneCallBack(string strValue);
36 ShowGroupOneCallBack showGroupOneCallBack;
37
38 //定义并声明操作"任务2"分组框的回调
39 private delegate void ShowGroupTwoCallBack(string strValue);
40 ShowGroupOneCallBack showGroupTwoCallBack;
41
42
43
44 /// <summary>
45 /// 提交
46 /// </summary>
47 /// <param name="sender"></param>
48 /// <param name="e"></param>
49 private void btn_OK_Click(object sender, EventArgs e)
50 {
51 //创建线程1
52 Thread thread1 = new Thread(new ThreadStart(ExecuteTsk1));
53 //启动线程1
54 thread1.Start();
55
56 //创建线程2
57 Thread thread2 = new Thread(new ThreadStart(ExecuteTsk2));
58 //启动线程2
59 thread2.Start();
60
61 }
62
63
64 private void ExecuteTsk1()
65 {
66 if (chbOne.Checked)
67 {
68 //3、实例化委托
69 writeToTextBox = new WriteToTextBox(WriteTextBox1);
70 //4、将委托作为方法的参数进行传递
71 WriteText(writeToTextBox);
72 //使用回调
73 this.gbJobOne.Invoke(showGroupOneCallBack, "任务1");
74 }
75 }
76
77 private void ExecuteTsk2()
78 {
79 if (chbTwo.Checked)
80 {
81 //3、实例化委托
82 writeToTextBox = new WriteToTextBox(WriteTextBox2);
83 //4、将委托作为方法的参数进行传递
84 WriteText(writeToTextBox);
85 //使用回调
86 this.gbJobTwo.Invoke(showGroupTwoCallBack, "任务2");
87 }
88 }
89
90 /// <summary>
91 /// 执行自定义委托
92 /// </summary>
93 /// <param name="writeMethod"></param>
94 private void WriteText(WriteToTextBox writeMethod)
95 {
96 string strData = this.txt_Input.Text;
97 writeMethod(strData);
98 }
99
100 /// <summary>
101 /// 给文本区1赋值
102 /// </summary>
103 /// <param name="strTxt"></param>
104 private void WriteTextBox1(string strTxt)
105 {
106 //使用回调
107 this.txtJobOne.Invoke(writeTxtJobOneCallBack, strTxt);
108 }
109
110 /// <summary>
111 /// 给文本区2赋值
112 /// </summary>
113 /// <param name="strTxt"></param>
114 private void WriteTextBox2(string strTxt)
115 {
116 //使用回调
117 this.txtJobTwo.Invoke(writeTxtJobTwoCallBack, strTxt);
118 }
119
120 /// <summary>
121 /// 窗体加载事件
122 /// </summary>
123 /// <param name="sender"></param>
124 /// <param name="e"></param>
125 private void FrmMain_Load(object sender, EventArgs e)
126 {
127 //设置文本框获取焦点
128 this.ActiveControl = this.txt_Input;
129
130 //实例化回调
131 writeTxtJobOneCallBack = new WriteTxtJobOneCallBack(WriteToTextJobOne);
132 writeTxtJobTwoCallBack = new WriteTxtJobOneCallBack(WriteToTextJobTwo);
133 showGroupOneCallBack = new ShowGroupOneCallBack(ShowGroupOne);
134 showGroupTwoCallBack = new ShowGroupOneCallBack(ShowGroupTwo);
135
136 }
137
138 /// <summary>
139 /// 操作文本区1的回调要执行的方法
140 /// </summary>
141 /// <param name="strValue"></param>
142 private void WriteToTextJobOne(string strValue)
143 {
144 this.txtJobOne.Text = strValue;
145 }
146
147 /// <summary>
148 /// 操作文本区2的回调要执行的方法
149 /// </summary>
150 /// <param name="strValue"></param>
151 private void WriteToTextJobTwo(string strValue)
152 {
153 this.txtJobTwo.Text = strValue;
154 }
155
156 /// <summary>
157 /// 操作"任务1"分组框的回调要执行的方法
158 /// </summary>
159 /// <param name="strValue"></param>
160 private void ShowGroupOne(string strValue)
161 {
162 this.gbJobOne.Text = strValue;
163 }
164
165 /// <summary>
166 /// 操作"任务2"分组框的回调要执行的方法
167 /// </summary>
168 /// <param name="strValue"></param>
169 private void ShowGroupTwo(string strValue)
170 {
171 this.gbJobTwo.Text = strValue;
172 }
173 }
174 }
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