Using browscap.ini with VB.Net - asp.net

Question

Since 2013 now (more than 3 years), I have been using http://www.useragentstring.com/ in my main VB.Net project to get browser name/version and OS name/version from user agent string to add statistics to my local web application.
But, recently, in last months, this web site has been unreliable with a lot of down times. So to avoid missing data in my statistics, I searched for a local solution instead of an online one. I found http://browscap.org/ is an old web site (since 1998) that still upload updated user agent information to this day (browscap.ini). It is designed for PHP, but I found a C# implementation there: https://www.gocher.me/C-Sharp-Browscap .
But as a VB.Net developper, I did not find any VB implementation for it. I googled a lot but with no success. Does anyone get one for VB.NET?

Answer 1

I finally get to convert the C# solution to VB.NET with some head scratching.
Public Class CompareByLength
Implements IComparer(Of String)
Private Function Compare(ByVal x As String, ByVal y As String) as Integer _
Implements IComparer(Of String).Compare
If x Is Nothing Then
If y Is Nothing Then
Return 0
Else
Return 1
End If
Else
If y Is Nothing Then
Return -1
Else
Dim retval As Integer = x.Length.CompareTo(y.Length)
If retval <> 0 Then
Return -retval
Else
return -x.CompareTo(y)
End If
End If
End If
End Function
End Class
Public Class BrowsCap
Private Declare Function GetPrivateProfileSectionNames Lib "kernel32.dll" Alias "GetPrivateProfileSectionNamesA" (ByVal lpReturnedString As Byte(), ByVal nSize As Integer, ByVal lpFileName As String) As Integer
Private Declare Function GetPrivateProfileSection Lib "kernel32.dll" Alias "GetPrivateProfileSectionA" (ByVal lpAppName As String, ByVal lpReturnedBuffer As Byte(), ByVal nSize As Integer, ByVal lpFileName As String) As Integer
Private Declare Function GetPrivateProfileString Lib "kernel32.dll" Alias "GetPrivateProfileStringA" (ByVal lpApplicationName As String, ByVal lpKeyName As String, ByVal lpDefault As String, ByVal lpReturnedBuffer As String, ByVal nSize As Integer, ByVal lpFileName As String) As Integer
Private path As String
Private sections As String()
Private Function GetSectionNames() As String()
Dim maxsize As Integer = 500
Do
Dim bytes(maxsize) As Byte
Dim size As Integer = GetPrivateProfileSectionNames(bytes, maxsize, path)
If size < maxsize - 2 Then
Dim Selected As String = Encoding.ASCII.GetString(bytes, 0, size - (IIf(size > 0, 1, 0)))
Return Selected.Split(New Char() {ControlChars.NullChar})
End If
maxsize = maxsize * 2
Loop
End Function
Public Sub IniFileName(ByVal INIPath As String)
path = INIPath
sections = GetSectionNames()
Array.Sort(sections, New CompareByLength())
End Sub
public Function IniReadValue(ByVal Section As String, ByVal Key As String) As String
Dim temp As New StringBuilder(255)
Dim i As Integer = GetPrivateProfileString(Section, Key, "", temp.ToString(), 255, path)
Return temp.ToString()
End Function
Private Function findMatch(ByVal Agent As String) As String
If sections IsNot Nothing Then
For Each SecHead As String In sections
If (SecHead.IndexOf("*", 0) = -1) And (SecHead.IndexOf("?", 0) = -1) And (SecHead = Agent) Then
If IniReadValue(SecHead, "parent") <> "DefaultProperties" Then
Return SecHead
End If
End If
Next
For Each SecHead As String In sections
Try
If (SecHead.IndexOf("*", 0) > -1) Or (SecHead.IndexOf("?", 0) > -1) Then
if Regex.IsMatch(Agent, "^" + Regex.Escape(SecHead).Replace("\*", ".*").Replace("\?", ".") + "$") Then
Return SecHead
End If
End If
Catch ex As Exception
'Console.WriteLine(ex)
End Try
Next
Return "*"
End If
Return ""
End Function
Public Function getValues(ByVal Agent As String) As NameValueCollection
Dim match As String = findMatch(Agent)
Dim col As NameValueCollection = New NameValueCollection()
Do
Dim entries() As string
Dim goon As Boolean = true
Dim maxsize As Integer = 500
While goon
Dim bytes(maxsize) As Byte
Dim size As Integer = GetPrivateProfileSection(match, bytes, maxsize, path)
If size < maxsize - 2
Dim section As String = Encoding.ASCII.GetString(bytes, 0, size - IIf(size > 0, 1, 0))
entries = section.Split(New Char() {ControlChars.NullChar})
goon = False
End If
maxsize = maxsize * 2
End While
match = ""
If entries.Length > 0 Then
For Each entry As String In entries
Dim ent As String() = entry.Split(New Char() {"="C})
If ent(0) = "Parent" Then
match = ent(1)
else if col(ent(0)) is nothing Then
col.Add(ent(0), ent(1))
End If
Next
End If
Loop While match <> ""
Return col
End Function
End Class
And here is how to use it:
Dim dict As Dictionary(Of String, Object) = New Dictionary(Of String, Object)
Dim bc As New BrowsCap
bc.IniFileName(Server.MapPath("/App_Data/lite_asp_browscap.ini"))
Dim Entry As NameValueCollection = bc.getValues(Request.UserAgent)
For Each s As String In Entry.AllKeys
dict.Add(s, Entry(s))
Next
' dict("Browser") will contains browser name like "IE" or "Chrome".
' dict("Version") will contains browser version like "11.0" or "56.0".
' dict("Platform") will contains OS name and version like "Win7".
The only thing left to do is to refresh my browscap.ini (or lite_asp_browscap.ini) sometimes (like once a week).