Tracing HTTP Redirects

Example to trace through HTTP redirects.

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Dim http As New Chilkat.Http()

Dim success As Boolean

'  Any string unlocks the component for the 1st 30-days.
success = http.UnlockComponent("Anything for 30-day trial")
If (success <> true) Then
    MsgBox(http.LastErrorText)
    Exit Sub
End If


Dim url As String
Dim html As String
Dim status As Long

url = "http://www.planyourweddingonline.co.za/"

'  The FollowRedirects property controls whether redirects
'  are automatically followed.  The default behavior is to
'  automatically follow redirects.

'  Explicitly set FollowRedirects so that redirects are NOT automatically taken:
http.FollowRedirects = false

'  Send the HTTP GET and return the content in a string.
html = http.QuickGetStr(url)
If (html = vbNullString ) Then
    MsgBox(http.LastErrorText)
End If


status = http.LastStatus
TextBox1.Text = TextBox1.Text & "HTTP Response Status: " _
     & status & vbCrLf

'  The FinalRedirectUrl property will contain the redirect URL
'  If FollowRedirects was equal to True, then all of the
'  intermediate redirects (if any) would be followed until
'  there were no more redirects.  However, because
'  FollowRedirects is not True, FinalRedirectUrl contains
'  the next redirect URL.
TextBox1.Text = TextBox1.Text & "Redirect URL: " _
     & http.FinalRedirectUrl & vbCrLf

Dim loopCount As Long
loopCount = 0

While (status = 302)
    url = http.FinalRedirectUrl
    html = http.QuickGetStr(url)
    If (html = vbNullString ) Then
        MsgBox(http.LastErrorText)
        Exit While
    End If

    status = http.LastStatus
    TextBox1.Text = TextBox1.Text & "Redirect URL: " _
         & http.FinalRedirectUrl & vbCrLf

    '  You may wish to check that if FinalRedirectUrl
    '  equals the URL just retrieved.  If so, then break out of the
    '  loop.  (This check is omitted in this example.)

    '  Instead, this example will prevent infinite loops by
    '  keeping a loopCount and only allows following a max
    '  of 10 redirects:
    loopCount = loopCount + 1
    If (loopCount > 10) Then
        Exit While
    End If


End While