How to check all content-type values?

I have some tasks where I have to open xml document in related application, so I had to know the content type values. I did not know that it could be checked in regedit :-)

so here is a way how we can look at it

HKEY_CLASSES_ROOT \ Mime \ Database \ Content Type \

f.x. for excel it will be like this

Print {Content-Type:application/vnd.ms-excel}
Print {Cache-Control: public, must-revalidate}
Print {Expires: Sat, 26 Jul 1997 05:00:00 GMT}
Print xml_output