我可以从用户代理获得Mac OS版本吗？

Question

I have an app in different Mac OS versions - one for el Capitan and up and one for all OS versions below that.

Users (unfortunately) don't always know that they're on el Cap or Sierra and have trouble figuring it out.

On my download page I'd like to show them (if possible) which version to download and hence I'd like to use the User Agent string to do this.

It seems it can contain phrases like "Intel Mac OS X 10_12_3" - is this reliable or is there a standard for this? Can't find it on Apple.com. And if it is - what kind of shape can I determine it from?

Answer 1

I suggest you match the regular expression

/OS X 10[_.](\d+)/

Some browsers use _ to separate the parts of the OS X release, while others use ., and this will match either format. The capture group will contain the OS X major release number. If it's 11 or higher then they should use the El Capitan version.