access a web site and compare version numbers

ok what i wanna do is make a script or something to update installers i have.

i want it to access the site for the program(or major geeks) compare version numbers and if the version number is greater download and replace the previous installer

is there a way to do this with vbs,javascript,or regular java?

(im currently in my class learning java right this moment but we still on loops)

 

Depends on where to find the version number. I'm pretty sure you have no access to read meta data of a file which is saved on a web server. You could download the source text of the web site and try to find the version# by using Regular Expressions or someting similar. But IMHO it's a feasible method but not a safe method. You have to write a separate algorithm for each web site, but it will fail if they change the layout.

It's no problem to get it from a local file via VBS or JS (I'm not familiar with Java, but it's probably not a big deal in Java).

 

ok thats what i was afraid of oh well its the manual way for now

maybe when my java class is done i can figure it out

 

This is a very bad idea btw, with out the site owners permission, because your if your app isn't written properly, it will be constantly grabbing data from what ever site your version checking on, increasing there bandwidth usage. Its best to check with a site owner or even some developers offer automated methods to check if they have new releases of files. Just something to keep in mind.

 

true but what im figuring is set it to run about once a week and after checking it would ask if i wanted to download the new version which would reduce server load and it wouldnt be running all the time

 

Just understand that, before running anything not directly human operated its nice to have the owners permission. If i see anything remotely automated running even weekly against my personal site it will trip alarms, and probably get ip banned from access. Just throwing that bit of caution at you. Sounds like your aware tho. Good Luck

 

true

 

Generaly i try to be helpful in my posts, but i haven't programmed sense vb6 lol. Good luck.

 

Haha, OK I see you cannot give up. This works (currently) for Firefox. Not sure whether you already installed it.

*.vbs

Code:

' local version
strFileFullName = "C:\Program Files\Mozilla Firefox\Firefox.exe"
strPropertyName = "ProductVersion"

' latest version
strURL = "http://www.mozilla.org/en-US/firefox/fx/"
strPattern = "http:\/\/download\.mozilla\.org\/\?product=firefox-\d+\.\d+\.\d+&os=win&lang=en-US"

' find local version
Set objFSO = CreateObject("Scripting.FileSystemObject")
strLocal = CreateObject("Shell.Application") _
  .NameSpace(objFSO.GetParentFolderName(strFileFullName)) _
  .ParseName(objFSO.GetFileName(strFileFullName)) _
  .ExtendedProperty(strPropertyName)

' find latest version in the internet
On Error Resume Next
Set objXMLHTTP = CreateObject("Microsoft.XMLHTTP")
objXMLHTTP.Open "GET", strURL, False
objXMLHTTP.Send
If (objXMLHTTP.readyState = 4 And objXMLHTTP.status = 200) Then
  Set objRegEx = New RegExp
  objRegEx.IgnoreCase = True
  objRegEx.Pattern = strPattern
  Set colMatches = objRegEx.Execute(objXMLHTTP.responseText)
  For Each oMatch In colMatches
    strLink = oMatch.Value
  Next
  Set colMatches = Nothing
Else
  WScript.Echo "Check your internet connection!"
  WScript.Quit
End If
Err.Clear
On Error Goto 0
Set objXMLHTTP = Nothing
objRegEx.Pattern = "\d+\.\d+\.\d+"
Set colMatches = objRegEx.Execute(strLink)
For Each oMatch In colMatches
  strCurrent = oMatch.Value
Next
Set colMatches = Nothing
Set objRegEx = Nothing

WScript.Echo "Local Firefox version: " & strLocal & _
  vbCrLf & "Latest Firefox version: " & strCurrent

It's simple to find out the local version by reading the extended properties of the exe file.

More complicated is to select it from the internet. I read the entire source text of the web site (strURL) and match it against a pattern via RegEx to get the download link which contains the version number. Then I extract it out of this string.

Regards
GermanOne

 

thank you german ill try it soon i gtg get breakfast and get to class im in college now =D