Use C # To implement a simple communication program similar to QQ

Using system;
Using system. drawing;
Using system. collections;
Using system. componentmodel;
Using system. Windows. forms;
Using system. Data;
Using system. IO;
Using system. net. Sockets;
Using system. Threading;
Namespace p2pchat
{
///
/// Summary of mainform.
///
Public class mainform: system. Windows. Forms. Form
{
Private system. Windows. Forms. Label label1;
Private system. Windows. Forms. Label label2;
Private system. Windows. Forms. textbox txtip;
Private system. Windows. Forms. textbox txtrecord;
Private system. Windows. Forms. textbox txtname;
Private system. Windows. Forms. Button btnsend;
Private system. Windows. Forms. textbox txtcontent;

Private tcplistener tcplster = new tcplistener (5566 );
System. Threading. threadstart listenport;
System. Threading. Thread Lister;
Private system. Windows. Forms. Label label3;
System. Windows. Forms. policyicon policyicon1;
// The icon displayed in the tray. I use the pet dog icon in QQ.
Private icon IMG = new icon (@ "C: \ openpet. ICO ");
System. Windows. Forms. contextmenu nmenu;
///
/// Required designer variables.
///
Private system. componentmodel. Container components = NULL;
Public mainform ()
{
//
// Required for Windows Form Designer support
//
Initializecomponent ();

// Do not display the maximize button
This. maximizebox = false;
// The task bar is not displayed when the value is minimized.
This. showintaskbar = false;
Listenport + = new threadstart (this. Listen );
Lister = new thread (listenport );
This. Closing + = new system. componentmodel. canceleventhandler (abortlister );
Initializenotifyicon ();
//
// Todo: add Any constructor code after initializecomponent calls
//
}
# Region initialize the tray component
Private void initializenotifyicon ()
{
Yyicon1 = new notifyicon ();
Policyicon1.icon = IMG;
Policyicon1.text = "LAN chat program ";
Policyicon1.visible = true;
Policyicon1.doubleclick + = new eventhandler (this. showmainform );

Menuitem [] menuarray = new menuitem [3];
Menuarray [0] = new menuitem ();
Menuarray [0]. Text = "display Main Window ";
Menuarray [0]. Click + = new eventhandler (this. showmainform );
Menuarray [0]. defaultitem = true;

Menuarray [1] = new menuitem ("-");

Menuarray [2] = new menuitem ();
Menuarray [2]. Text = "quit ";
Menuarray [2]. Click + = new eventhandler (this. exitsystem );

Nmenu = new contextmenu (menuarray );
Policyicon1.contextmenu = nmenu;
}
// Display the Main Window
Private void showmainform (Object sender, system. eventargs E)
{
This. windowstate = system. Windows. Forms. formwindowstate. normal;
}
// Exit the program
Private void exitsystem (Object sender, system. eventargs E)
{
Policyicon1.visible = false;
This. Close ();
}
# Endregion
///
/// Clear all resources in use.
///
Protected override void dispose (bool disposing)
{
If (disposing)
{
If (components! = NULL)
{
Components. Dispose ();
}
}
Base. Dispose (disposing );
}
# Region code generated by Windows Form Designer
///
/// The designer supports the required methods-do not use the code editor to modify
/// Content of this method.
///
Private void initializecomponent ()
{

This. label1 = new system. Windows. Forms. Label ();
This.txt IP = new system. Windows. Forms. Textbox ();
This.txt record = new system. Windows. Forms. Textbox ();
This. label2 = new system. Windows. Forms. Label ();
This.txt name = new system. Windows. Forms. Textbox ();
This. btnsend = new system. Windows. Forms. Button ();
This.txt content = new system. Windows. Forms. Textbox ();
This. label3 = new system. Windows. Forms. Label ();
This. suspendlayout ();
//
// Label1
//
This. label1.location = new system. Drawing. Point (16,232 );
This. label1.name = "label1 ";
This. label1.size = new system. Drawing. Size (72, 23 );
This. label1.tabindex = 0;
This. label1.text = "target address :";
This. label1.textalign = system. Drawing. contentalignment. middlecenter;
//
// Txtip
//
This.txt IP. Anchor = (system. Windows. Forms. anchorstyles) (system. Windows. Forms. anchorstyles. Left | system. Windows. Forms. anchorstyles. Right )));
This.txt IP. Location = new system. Drawing. Point (80,232 );
This.txt IP. Name = "txtip ";
This.txt IP. size = new system. Drawing. Size (200, 21 );
This.txt IP. tabindex = 1;
This.txt IP. Text = "";
//
// Txtrecord
//
This.txt record. Anchor = (system. Windows. Forms. anchorstyles) (system. Windows. Forms. anchorstyles. Left | system. Windows. Forms. anchorstyles. Right )));
This.txt record. Location = new system. Drawing. Point (16, 32 );
This.txt record. multiline = true;
This.txt record. Name = "txtrecord ";
This.txt record. readonly = true;
This.txt record. scrollbars = system. Windows. Forms. scrollbars. vertical;
This.txt record. size = new system. Drawing. Size (264,176 );
This.txt record. tabindex = 4;
This.txt record. Text = "";
//
// Label2
//
This. label2.location = new system. Drawing. Point (24,256 );
This. label2.name = "label2 ";
This. label2.size = new system. Drawing. Size (48, 23 );
This. label2.tabindex = 5;
This. label2.text = :";
This. label2.textalign = system. Drawing. contentalignment. middlecenter;
//
// Txtname
//
This.txt name. Location = new system. Drawing. Point (80,256 );
This.txt name. Name = "txtname ";
This.txt name. size = new system. Drawing. Size (88, 21 );
This.txt name. tabindex = 6;
This.txt name. Text = "";
//
// Btnsend
//
This. btnsend. Location = new system. Drawing. Point (200,256 );
This. btnsend. Name = "btnsend ";
This. btnsend. size = new system. Drawing. Size (64, 23 );
This. btnsend. tabindex = 0;
This. btnsend. Text = "send ";
This. btnsend. Click + = new system. eventhandler (this. btnsend_click );
//
// Txtcontent
//
This.txt content. Anchor = (system. Windows. Forms. anchorstyles) (system. Windows. Forms. anchorstyles. Bottom | system. Windows. Forms. anchorstyles. Left)
| System. Windows. Forms. anchorstyles. Right )));
This.txt content. Location = new system. Drawing. Point