Getting HTTP data from server

  • Thread starter Thread starter Nuno Magalhaes
  • Start date Start date
N

Nuno Magalhaes

Hello,

I've got a small application that tries to read HTML data without the
HTTPWebResponse and Request methods and I guess the server is closing
the connection after a while.

Here is my sample code:
----------------------------------------------------
IPHostEntry iphe=Dns.GetHostByName("www.google.com");
string ipString=iphe.AddressList[0].ToString();
TcpClient tcpClient=new TcpClient(ipString,80);
NetworkStream ns=tcpClient.GetStream();
StreamReader sr=new StreamReader(ns);
StreamWriter sw=new StreamWriter(ns);
sw.WriteLine("GET /\r\n\r\n");
string serverHtml=sr.ReadLine();
----------------------------------------------------
The problem is that sr.ReadLine() returns null after a while... since
I'm trying to access an "object null reference". Is there any problems
in the code above?
I tried also:
sw.WriteLine("GET /\n\n");
sw.WriteLine("GET / HTTP/1.1\r\nConnection: Keep-Alive\n\n");
sw.WriteLine("GET / HTTP/1.1\nConnection: Keep-Alive\n");

No results. The server never responds. Can anyone tell me what I'm
doing wrong?

Thanks in advance,
Nuno Magalhaes.
 
Nuno said:
Hello,

I've got a small application that tries to read HTML data without the
HTTPWebResponse and Request methods and I guess the server is closing
the connection after a while.

Here is my sample code:
----------------------------------------------------
IPHostEntry iphe=Dns.GetHostByName("www.google.com");
string ipString=iphe.AddressList[0].ToString();
TcpClient tcpClient=new TcpClient(ipString,80);
NetworkStream ns=tcpClient.GetStream();
StreamReader sr=new StreamReader(ns);
StreamWriter sw=new StreamWriter(ns);
sw.WriteLine("GET /\r\n\r\n");
string serverHtml=sr.ReadLine();
----------------------------------------------------
The problem is that sr.ReadLine() returns null after a while... since
I'm trying to access an "object null reference". Is there any problems
in the code above?
I tried also:
sw.WriteLine("GET /\n\n");
sw.WriteLine("GET / HTTP/1.1\r\nConnection: Keep-Alive\n\n");
sw.WriteLine("GET / HTTP/1.1\nConnection: Keep-Alive\n");

No results. The server never responds. Can anyone tell me what I'm
doing wrong?
Click to expand...

None of your HTTP requests is valid. Why don't you use
System.Net.WebClient for such mundane tasks?

Cheers,
 
Because WebClient doesn't allow me to time certain parameters of QoS
such as: Time to resolve DNS, Time to Connect, Time to Receive Data,
between others...

Any hints on how can I know if a web page is completly read? Since the
stream or the socket.Available sometimes is 0. May be busy with another
pages and I have to wait for data with a message box between send and
receive. I don't know when a page is completly read since I don't get
the Content-Length parameter in the HTTP response header. Maybe I'm not
sending all the parameters to the server also.

Here's my sample code:
****************************************************
-socket.Connect(endpoint);
-byte[] msg=Encoding.UTF8.GetBytes("GET / HTTP/1.1\n\n");
byte[] bytes=new byte[65536];
int i=socket.Send(msg,0,msg.Length,SocketFlags.None);
MessageBox.Show("Sent "+i.ToString()+" bytes. Available:
"+socket.Available.ToString()+" bytes.");
socket.Receive(bytes,0,socket.Available,SocketFlags.None);
TrafficLogTextBox.Text+=Encoding.UTF8.GetString(bytes);
TrafficLogTextBox.Text+="\r\n";
MessageBox.Show(Encoding.UTF8.GetString(bytes));
 
Wouldn't hurt to flush after writing data to the socket - 9 times out of
10 this is what keeps me going nutz until i remember to flush...
 
Back
Top