Winsock connects but gets no response from server (stays on waiting status)

[the_one2003a]

Hi,

I'm new to winsock and VB, What I want to do is simple. Just to get a webpage data from a site by using winsock (using an example source code which works in other PCs very well), the program connects to website and prints "waiting for response" but never gets the response (DataArrival never gets fired), I have attached the program, So what may cause this error?

[vbpHacker]

One reason might be you're sending HTTP/1.0 instead of 1.1, most servers are using the 1.1 protocol but they should still work with 1.0.

You're also not supplying much information in the HTTP header, and the Connection: Keep -Alive should be: Connection: Keep-Alive (no space before the dash).

Your code is also messy... some variables not declared, others declared as variants, no indenting, etc. Makes debugging a lot harder. I cleaned up the code a little and made a few changes, see if this works... If it doesn't, post the URL of the site that you tried.

Option Explicit

Private HTTPData As String

Private Sub Status(ByRef strStatus As String)
    With txtStatus
        .SelStart = Len(.Text)
        .SelText = strStatus & vbCrLf
    End With
End Sub

Private Sub Command1_Click()
    With Win
        HTTPData = vbNullString 'Reset/erase data
        .Close
        .Connect Text2.Text, 80
    End With
    
    Text1.Alignment = vbLeftJustify
    Text1.Text = Text2.Text & " Informations:" & vbCrLf & vbCrLf
    Status "Connecting..."
End Sub

Private Sub Label3_Click()
    Do While Me.Height > 255
        Me.Height = Me.Height - 15
        DoEvents
    Loop
    
    Do While Me.Width > 15
        Me.Width = Me.Width - 15
        DoEvents
    Loop
    
    Unload Me 'Don't use End
End Sub

Private Sub Label4_Click()
    Me.WindowState = vbMinimized
End Sub

Private Sub txtStatus_Change()
    txtStatus.SelStart = Len(txtStatus)
End Sub

Private Sub Win_Close()
    Win.Close
    Status "Connection Closed."
    AnalyseData HTTPData
End Sub

Private Sub Win_Connect()
    Dim Packet As String
    
    Status "Connected."
    
    Text1 = Text1 & "Host Name: " & Win.RemoteHost & vbCrLf
    Text1 = Text1 & "IP: " & Win.RemoteHostIP & vbCrLf
    
    Packet = "GET / HTTP/1.1" & vbCrLf
    Packet = Packet & "User-Agent: HTTPScanner" & vbCrLf
    Packet = Packet & "Accept: *.*" & vbCrLf
    Packet = Packet & "Connection: Close" & vbCrLf & vbCrLf
    
    Win.SendData Packet
End Sub

Function AnalyseData(strData)
    Dim s As Long, l As String, info As String, inf() As String
    Dim i As Long
    
    s = InStr(strData, "Content-Length:") + 16
    
    l = Mid(strData, s, InStr(s, strData, vbCrLf) - s)
    
    info = Left(strData, InStr(strData, vbCrLf & vbCrLf)) 'Left(strData, Len(strData) - l)
    If InStr(info, "200 OK") <> 0 Then Status "Sent packet was accepted."
    
    inf = Split(info, vbCrLf)
    
    Text1 = Text1 & "Home Page Size: " & l & " bytes" & vbCrLf
    For i = 0 To UBound(inf)
    If InStr(inf(i), "HTTP/") = 0 And InStr(inf(i), "Content-Length: ") = 0 And InStr(inf(i), "Connection: ") = 0 And inf(i) <> "" Then
    Text1 = Text1 & inf(i) & vbCrLf
    End If
    Next
    
hell:
    Text1 = Left(Text1, Len(Text1) - 2)
    Status "Completed."
End Function

Private Sub Win_DataArrival(ByVal bytesTotal As Long)
    Dim Data As String
    Status "Receiving data..."
    Win.GetData Data, vbString, bytesTotal
    
    HTTPData = HTTPData & Data
End Sub

Private Sub Win_Error(ByVal Number As Integer, Description As String, ByVal Scode As Long, ByVal Source As String, ByVal HelpFile As String, ByVal HelpContext As Long, CancelDisplay As Boolean)
    Status "Error"
    Win.Close
End Sub

Private Sub Win_SendComplete()
    Status "Packet sent. Waiting for response."
End Sub

Private Sub Win_SendProgress(ByVal bytesSent As Long, ByVal bytesRemaining As Long)
    Status "Sending Packet..."
End Sub

[the_one2003a]

Actually I didn't written the code just got from a website to test. Changed the code as above and tested but when I click to connect and get the webpage it prints the following (testing www.google.com):

Sending Packet...
Packet sent. Waiting for response.

But no response and then prints 'Error'. I think it is something related to my PC configuration since I have tested some other VB programs which use Winsock and they have the same problem and just wait for response which never retrieve.
So any suggestions on how to find the problem and solving it?

[DigiRev]

You could try downloading the SP6 service pack if you don't already have it:
http://www.microsoft.com/downloads/d...displaylang=en

The code (despite how crappy it is) still works fine for me.

[the_one2003a]

I installed SP6 but still no difference, so how can I debug this problem to know what causes this?