Lightweight Device-Detection in ASP
Device detection is the first step in performing content adaptation. Here we cover lightweight device detection using classic ASP (VBScript). This is based on the PHP version found here. It is a simple script which will detect most mobile browsers. However, if you need more information about the properties of the device such as screen width and height, image format support etc. so that you can tailor your content to specific devices, then you need something more than this. In this case you should consider using a full device properties database such as DeviceAtlas.
This script attempts to match the requesting UA string against about 90 well-known mobile browser UA string snippets, and a couple of special cases. It also checks some of the other HTTP headers for hints that the client is mobile.
If you simply need to decide if the client is a mobile or desktop browser, then this script is for you! If you need to know more about a requesting device, try DeviceAtlas. Improvements and suggestions are very welcome.
<% Option Explicit Dim user_agent, mobile_browser, Regex, match, mobile_agents, mobile_ua, i, size user_agent = Request.ServerVariables("HTTP_USER_AGENT") mobile_browser = 0 Set Regex = New RegExp With Regex .Pattern = "(up.browser|up.link|mmp|symbian|smartphone|midp|wap|phone|windows ce|pda|mobile|mini|palm)" .IgnoreCase = True .Global = True End With match = Regex.Test(user_agent) If match Then mobile_browser = mobile_browser+1 If InStr(Request.ServerVariables("HTTP_ACCEPT"), "application/vnd.wap.xhtml+xml") Or Not IsEmpty(Request.ServerVariables("HTTP_X_PROFILE")) Or Not IsEmpty(Request.ServerVariables("HTTP_PROFILE")) Then mobile_browser = mobile_browser+1 end If mobile_agents = Array("w3c ", "acs-", "alav", "alca", "amoi", "audi", "avan", "benq", "bird", "blac", "blaz", "brew", "cell", "cldc", "cmd-", "dang", "doco", "eric", "hipt", "inno", "ipaq", "java", "jigs", "kddi", "keji", "leno", "lg-c", "lg-d", "lg-g", "lge-", "maui", "maxo", "midp", "mits", "mmef", "mobi", "mot-", "moto", "mwbp", "nec-", "newt", "noki", "oper", "palm", "pana", "pant", "phil", "play", "port", "prox", "qwap", "sage", "sams", "sany", "sch-", "sec-", "send", "seri", "sgh-", "shar", "sie-", "siem", "smal", "smar", "sony", "sph-", "symb", "t-mo", "teli", "tim-", "tosh", "tsm-", "upg1", "upsi", "vk-v", "voda", "wap-", "wapa", "wapi", "wapp", "wapr", "webc", "winw", "winw", "xda", "xda-") size = Ubound(mobile_agents) mobile_ua = LCase(Left(user_agent, 4)) For i=0 To size If mobile_agents(i) = mobile_ua Then mobile_browser = mobile_browser+1 Exit For End If Next If mobile_browser>0 Then Response.Write("Mobile!") Else Response.Write("Not mobile!") End If %>
To use this script, simply include it in any page for which you wish to determine whether the client is mobile or desktop.
Note that this script uses Option Explicit. If you want to use this script with code that does not use Option Explicit, you should comment out the first two lines to avoid compilation errors.
Posted by xyz 1 year ago
ASP.NET determines the capabilities of every browser which sends requests to the server independant of if the request originates from a mobile device or a desktop computer. If browsers are detected correctly and mobile devices are identified depends on the configuration of the server.
Posted by admin 1 year ago
Thanks for the news ;-) There are of course still many sites stilling using classic asp - it is these we are catering for here rather than ASP.NET developers.
Posted by Anonymous (not verified) 1 year ago
i'm using below function
----------------------------------
Function isMobile (ua,accept)
If(_
instr(accept,"text/vnd.wap.wml")>0 _
or instr(Lcase(ua),"symbian")>0 _
or instr(Lcase(ua),"series")>0 _
or instr(Lcase(ua),"nokia")>0 _
or instr(Lcase(ua),"mot-")>0 _
or instr(Lcase(ua),"motorola")>0 _
or instr(Lcase(ua),"lg-")>0 _
or instr(Lcase(ua),"lge")>0 _
or instr(Lcase(ua),"nec-")>0 _
or instr(Lcase(ua),"lg/")>0 _
or instr(Lcase(ua),"samsung")>0 _
or instr(Lcase(ua),"sie-")>0 _
or instr(Lcase(ua),"sec-")>0 _
or instr(Lcase(ua),"sgh-")>0 _
or instr(Lcase(ua),"sonyericsson")>0 _
or instr(Lcase(ua),"sharp")>0 _
or instr(Lcase(ua),"windows ce")>0 _
or instr(Lcase(ua),"portalmmm")>0 _
or instr(Lcase(ua),"o2-")>0 _
or instr(Lcase(ua),"docomo")>0 _
or instr(Lcase(ua),"philips")>0 _
or instr(Lcase(ua),"panasonic")>0 _
or instr(Lcase(ua),"sagem")>0 _
or instr(Lcase(ua),"smartphone")>0 _
or instr(Lcase(ua),"up.browser")>0 _
or instr(Lcase(ua),"up.link")>0 _
or instr(Lcase(ua),"googlebot-mobile")>0 _
or instr(Lcase(ua),"googlebot")>0 _
or instr(Lcase(ua),"slurp")>0 _
or instr(Lcase(ua),"spring")>0 _
or instr(Lcase(ua),"alcatel")>0 _
or instr(Lcase(ua),"sendo")>0 _
or instr(Lcase(ua),"blackberry")>0 _
or instr(Lcase(ua),"opera mini")>0 _
or instr(Lcase(ua),"opera 2")>0 _
or instr(Lcase(ua),"netfront")>0 _
or instr(Lcase(ua),"mobilephone mm")>0 _
or instr(Lcase(ua),"vodafone")>0 _
or instr(Lcase(ua),"avantgo")>0 _
or instr(Lcase(ua),"palmsource")>0 _
or instr(Lcase(ua),"siemens")>0 _
or instr(Lcase(ua),"toshiba")>0 _
or instr(Lcase(ua),"i-mobile")>0 _
or instr(Lcase(ua),"asus")>0 _
or instr(Lcase(ua),"ice")>0 _
or instr(Lcase(ua),"kwc")>0 _
or instr(Lcase(ua),"htc")>0 _
or instr(Lcase(ua),"softbank")>0 _
or instr(Lcase(ua),"mozilla/5.0 (x11; u; linux i686; en-us; rv:1.8.0.7) gecko/20060909 firefox/1.5.0.7")>0 _
or instr(Lcase(ua),"playstation")>0 _
or instr(Lcase(ua),"nitro")>0 _
or instr(Lcase(ua),"iphone")>0 _
or instr(Lcase(ua),"ipod")>0 _
or instr(Lcase(ua),"google wireless transcoder")>0 _
or instr(Lcase(ua),"t-mobile")>0 _
or instr(Lcase(ua),"obigo")>0 _
or instr(Lcase(ua),"brew")>0 _
or instr(Lcase(ua),"yahooseeker")>0 _
or instr(Lcase(ua),"msmobot")>0 _
or instr(Lcase(ua),"novarra")>0 _
or instr(Lcase(ua),"skp")>0 _
or instr(Lcase(ua),"openweb")>0 _
) _
Then
isMobile=True
else
isMobile=False
end if
End function
Posted by Kevin K (not verified) 1 year ago
You might want to optimize that a bit. ASP does not short-circuit any logical tests in an IF statement. All the tests will be done even if a match is found on the first. You should do the lcase() before the statement and maybe have a separate IF statement for the most common browsers first.
Posted by sixseraphim (not verified) 1 year ago
Can I use this code so that when a mobile user is detected that it redirects them to my more mobile friendly website?
Posted by admin 1 year ago
You sure can!
Posted by William Ramirez (not verified) 1 year ago
Doesn't work with opera, detects it as mobile even when it is a desktop.
Posted by WilliamStam (not verified) 1 year ago
mobile_agents = Array("w3c ", "acs-", "alav", "alca", "amoi", "audi", "avan", "benq", "bird", "blac", "blaz", "brew", "cell", "cldc", "cmd-", "dang", "doco", "eric", "hipt", "inno", "ipaq", "java", "jigs", "kddi", "keji", "leno", "lg-c", "lg-d", "lg-g", "lge-", "maui", "maxo", "midp", "mits", "mmef", "mobi", "mot-", "moto", "mwbp", "nec-", "newt", "noki", "oper", "palm", "pana", "pant", "phil", "play", "port", "prox", "qwap", "sage", "sams", "sany", "sch-", "sec-", "send", "seri", "sgh-", "shar", "sie-", "siem", "smal", "smar", "sony", "sph-", "symb", "t-mo", "teli", "tim-", "tosh", "tsm-", "upg1", "upsi", "vk-v", "voda", "wap-", "wapa", "wapi", "wapp", "wapr", "webc", "winw", "winw", "xda", "xda-")
look for the one "oper" i changed mine to "operamini"
Posted by shaunjbutler 1 year ago
How could you allow mobile users to visit the full site if they wanted without being automatically redirected back to the mobile site?
Posted by wulser 1 year ago
Nice article!
As admin stated earlier, many sites are still using ASP. Mine is one of them.
In reply to shaunjbutler's question, even if it was posted long ago, I can tell you that I simply changed the very last part of the code:
If mobile_browser>0 Then Response.Write("Mobile!") Else Response.Write("Not mobile!") End IfTo
If mobile_browser>0 Then Response.Redirect("*/looksmobile.asp") Else Response.Redirect("www.ourstandardwebsite.com") End IfThe looksmobile.asp site presents the user with a choice whether or not they want to view the mobile version of the site. Then saves their choice in a cookie, and sends them to their preferred site in the future.
Posted by stockstorm 1 year ago
Can I use this with an existing desktop browser website? The problem is, the website is in ASP.Net.
Posted by taomark 51 weeks ago
The script also doesn't work with my phone. It's a Sony Ericsson C902 with NetFront browser (a lot of new phones have similar technology). Problem is, this mobile browser returns a value for mobile_ua as "mozi" and therefore thinks it's a desktop Mozilla variant.
I know that mobile redirects work on my phone since pages like Google and bbc.co.uk implement it successfully. Any ideas? I only have the one phone on which to test my proposed mobile site so it's annoying that I can't get it to work!!
Posted by taomark 51 weeks ago
If it helps, the HTTP_USER_AGENT for my phone is:
Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.0.7) Gecko/20060909 Firefox/1.5.0.7 MG(Novarra-Vision/7.3)
Posted by ruadhan 51 weeks ago
Hmmm, it looks like there is a transcoder messing up your UA string:
The
(Novarra-Vision/7.3)bit gives it away...The usual UA strings for that device can be seen at the bottom of this page .
Ruadhan O'DonoghuemobiForge
Posted by taomark 51 weeks ago
Fair point, but the first two strings (at the bottom of that reference page) would surely also return a value for mobile_ua of "mozi" and therefore if my UA string was one of them, I'd have the same problem. Or am I reading that wrong?
Posted by taomark 51 weeks ago
BTW, I have checked with 3 of my friends who all have the same model of phone and all 3 display the same UA string as mine! Which, as you pointed out, isn't listed on the page you referenced. So either the UA strings on that page are out of date, or C902 phones are now displaying something different! Very annoying....
Posted by ruadhan 51 weeks ago
It's likely that you are all connecting to the Internet via the same transcoding proxy. What operator are you with?
Ruadhan O'DonoghuemobiForge
Posted by ruadhan 51 weeks ago
In this case, I would edit the line
to include the string Netfront:
Although it won't work where your UA has been mangled by a transcoder.
Ruadhan O'DonoghuemobiForge
Posted by taomark 51 weeks ago
We're all with Vodafone. At the moment I'm using a workaround by inserting the line:
If InStr(Request.ServerVariables("HTTP_USER_AGENT"), "Novarra") > 0 Then mobile_browser = mobile_browser+1
after the for...next loop. This will detect all Novarra devices (which are mobile or handheld anyway). Not the best solution but it works for now. Just wondered if there was a neater way of doing this, especially since there might be other mangled UA strings out there!
Posted by ruadhan 51 weeks ago
Vodafone uses the novarra transcoder...
Welcome to the world of transcoders - unsolicited transcoding is the bane of mobile web developers, and the mere mention of them is enough to cause blood vessels to burst in some developer circles.
Usually you can change the APN setting of your phone so that you don't go via the Vodafone transcoder. However, the average user won't know how to do this, or even what an APN is, or even what a transcoder is, or that something unintended by the content provider is happening... In Ireland, the APN:
live.vodafone.iegoes via the transcoder, whereasisp.vodafone.iedoes not transcode.Same applies in the UK as far as I know, but I'm not sure of the details of the Vodafone UK APNs.
If you felt compelled, you might visit http://ta-da.mobi to test your phone after you update your APN setting.
Ruadhan O'DonoghuemobiForge
Posted by cw622 31 weeks ago
in the above code
> mobile_agents = Array
I don't see the iphone listed as an agent?? however it detects the iphone as a mobile device.
What agent defines an Iphone?
I don't want to treat the Iphone as a mobile device
Posted by felipetv 28 weeks ago
Agent of my Blackberry 8310 Curve:
HTTP_USER_AGENT - Mozilla/4.0 (compatible; MSIE6.0; Windows NT 5.1; SV1)
Help...
Posted by mwitcomb 25 weeks ago
How would I amend the original script so that if the source was an iPHONE it would not include it as a mobile device, as all this shows is XML !!
Posted by ruadhan 25 weeks ago
You could try adding the string "ipho" to the list of strings above to check for - I've no idea if this will conflict with any desktop browser UAs though
Ruadhan O'DonoghuemobiForge
Posted by Thorandor 16 weeks ago
Hiya,
Just a quick note, if you are using the script posted in the 3rd comment you need to make sure that you do not use this line:
or instr(Lcase(ua),"ice")>0Reason is that this may cause issues with IE:
Alex