Read bytes from TCP socket in Delphi

To read bytes from a TCP socket in Delphi, you can use various components or libraries that provide TCP/IP functionality. One of the commonly used components is the TTCPBlockSocket from the Synapse library. Below is a basic example of reading bytes from a TCP socket using Synapse:

1. Download Synapse: Download the Synapse library from its official repository on GitHub: https://github.com/synopse/mORMot.
2. Add Synapse to Your Project:
   • Extract the Synapse archive.
   • Add the necessary Synapse units to your Delphi project.
3. Example Code: Below is an example that demonstrates how to create a TCP socket, connect to a server, and read bytes from the socket.
   
   Delphi/Pascal

   unit MainUnit; interface uses System.SysUtils, System.Classes, Vcl.Forms, blcksock, synsock; type TForm1 = class(TForm) procedure FormCreate(Sender: TObject); procedure FormDestroy(Sender: TObject); private TCPClient: TTCPBlockSocket; procedure ConnectToServer; procedure ReadBytesFromSocket; public { Public declarations } end; var Form1: TForm1; implementation {$R *.dfm} procedure TForm1.FormCreate(Sender: TObject); begin TCPClient := TTCPBlockSocket.Create; ConnectToServer; ReadBytesFromSocket; end; procedure TForm1.FormDestroy(Sender: TObject); begin TCPClient.Free; end; procedure TForm1.ConnectToServer; begin try // Connect to the server TCPClient.Connect(‘127.0.0.1′, ’80’); // Handle successful connection except // Handle connection error end; end; procedure TForm1.ReadBytesFromSocket; var Buffer: TBytes; begin try SetLength(Buffer, 1024); // Set the buffer size as needed // Read bytes from the socket TCPClient.RecvBufferEx(Buffer, Length(Buffer)); // Process the received bytes (example: display in a memo) Memo1.Lines.Add(‘Received Bytes: ‘ + string(TEncoding.ASCII.GetString(Buffer))); except // Handle read error end; end; end.

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   unit MainUnit;   interface   uses   System.SysUtils, System.Classes, Vcl.Forms, blcksock, synsock;   type   TForm1 = class(TForm)     procedure FormCreate(Sender: TObject);     procedure FormDestroy(Sender: TObject);   private     TCPClient: TTCPBlockSocket;     procedure ConnectToServer;     procedure ReadBytesFromSocket;   public     { Public declarations }   end;   var   Form1: TForm1;   implementation   {$R *.dfm}   procedure TForm1.FormCreate(Sender: TObject); begin   TCPClient := TTCPBlockSocket.Create;   ConnectToServer;   ReadBytesFromSocket; end;   procedure TForm1.FormDestroy(Sender: TObject); begin   TCPClient.Free; end;   procedure TForm1.ConnectToServer; begin   try     // Connect to the server     TCPClient.Connect(‘127.0.0.1’, ’80’);     // Handle successful connection   except     // Handle connection error   end; end;   procedure TForm1.ReadBytesFromSocket; var   Buffer: TBytes; begin   try     SetLength(Buffer, 1024); // Set the buffer size as needed       // Read bytes from the socket     TCPClient.RecvBufferEx(Buffer, Length(Buffer));       // Process the received bytes (example: display in a memo)     Memo1.Lines.Add(‘Received Bytes: ‘ + string(TEncoding.ASCII.GetString(Buffer)));   except     // Handle read error   end; end;   end.

   
   In this example:
   • ConnectToServer connects to a server (adjust the IP address and port as needed).
   • ReadBytesFromSocket reads bytes from the connected socket and displays them in a memo.

   Make sure to handle exceptions appropriately and adjust the code based on your specific requirements. The example assumes that the server is running on the localhost (127.0.0.1) and the port is 80. Modify these values based on your server configuration.

   Always check the documentation of the libraries you use and ensure compatibility with your Delphi version.