TCP聊天工具的实现

　　由于本人天生愚钝，所以关于聊天工具的编程一直都没学会，尽管网上教程一大堆，但是关于IdTCPClient  IdTCPServer 的不多，今天终于学会一些，分享给像我一样纠结的小伙伴，下一步学习多线程的聊天工具！

　　界面如图：memo 2个  button 3个  labelEdit 3个 IdTCPClient  1个   IdTCPServer 1个　

　

　代码如下：

　

 unit Unit1;
 
 interface
 
 uses
   Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
   Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.ExtCtrls, Vcl.StdCtrls,
   IdCustomTCPServer, IdTCPServer, IdBaseComponent, IdComponent, IdTCPConnection,
   IdTCPClient, IdContext,IdGlobal;
 
 type
   TForm1 = class(TForm)
     Memo1: TMemo;
     GroupBox1: TGroupBox;
     LabeledEdit1: TLabeledEdit;
     LabeledEdit2: TLabeledEdit;
     Button2: TButton;
     Button3: TButton;
     Label1: TLabel;
     Memo2: TMemo;
     IdTCPClient1: TIdTCPClient;
     IdTCPServer1: TIdTCPServer;
     GroupBox2: TGroupBox;
     LabeledEdit3: TLabeledEdit;
     Button1: TButton;
     procedure Button1Click(Sender: TObject);
     procedure Button2Click(Sender: TObject);
     procedure IdTCPServer1Connect(AContext: TIdContext);
     procedure Button3Click(Sender: TObject);
     procedure IdTCPServer1Execute(AContext: TIdContext);
     procedure FormClose(Sender: TObject; var Action: TCloseAction);
   private
     { Private declarations }
   public
     { Public declarations }
   end;
 
 var
   Form1: TForm1;
 
 implementation
 
 {$R *.dfm}
 
 procedure TForm1.Button1Click(Sender: TObject);  //监听
 begin
   IdTCPServer1.DefaultPort := StrToInt(LabeledEdit3.Text); //本地端口
   IdTCPServer1.Active := True;                             //打开监听
 end;
 
 procedure TForm1.Button2Click(Sender: TObject);   //远程连接
 begin
   if not IdTcpClient1.Connected then
   begin
   IdTCPClient1.Host := LabeledEdit1.Text;
   IdTCPClient1.Port := StrToInt(LabeledEdit2.Text);
   IdTCPClient1.Connect;
   IdTCPClient1.IOHandler.DefStringEncoding := IndyTextEncoding_UTF8(); //中文处理   uses   IdGlobal;
   end;
 end;
 
 procedure TForm1.IdTCPServer1Connect(AContext: TIdContext);   //有用户连接时候通知
 begin
   Memo1.Lines.Add('有朋友连接：');
   Memo1.Lines.Add('  ');
   AContext.Connection.IOHandler.DefStringEncoding := IndyTextEncoding_UTF8(); //中文处理    uses   IdGlobal;
 end;
 
 procedure TForm1.Button3Click(Sender: TObject);   //发送信息
 begin
   IdTCPClient1.IOHandler.writeln('皮皮说：'+ Memo2.Text);
 end;
 
 procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction); //关闭时断开连接
 begin
   IdTcpClient1.Disconnect;
 end;
 
 procedure TForm1.IdTCPServer1Execute(AContext: TIdContext);  //接收信息
 var
   recstr:string;
 begin
   recstr := AContext.Connection.IOHandler.ReadLn;
   Memo1.Lines.Add(recstr);
 end;
 
 end.