Differentiate IE7 browser and browser in IE7 compatibility mode
browser-detection, compatibility, internet-explorer, javascript
Solution
For at least IE8 and IE9, you can check whether `navigator.userAgent` has the substring `Trident` in it. An IE8+ always has a `Trident` in its user-agent, where an IE7 doesn't. See this answer and the MSDN link in it.
IE10 seems trickier: it is reported in the comments below that `Trident` is not always present with IE7 emulation mode. Probably the OS string (eg. `Windows NT 6.2`) will still reveal IE10, if IE10 will not be available on any platform where IE7 is available.
Please also note that the HTTP `User-Agent` header might not always match `navigator.userAgent`. This is the case at least with IE9 that has compatiblity mode on (sends an IE7 `User-Agent` header) but detects something like `IE=Edge` in the response (`navigator.userAgent` turns back to IE9).
Problem
Can I differentiate if client's browser is IE7 or e.g. IE9 in IE7 compatibility mode? I'm trying to figure out if I can do a JS check on my site which would recognize two different things and do different stuff depending on the result - that browser is IE7 - that browser is in IE7 compatibility mode I have the first condition working correctly as it's pretty much said everywhere how to do it. Not sure about the second one and/or combination of both.