The best approach for your friend is to sponsor her as fiance while she is in China. This way CIC will process it very quick (10 months, personal experience), because of the ethical reason; then he can get back to China to get marry and return to Canada together.
It is very complicated if the applicant is in Canada applying for immigrant status, the whole process could go upto 18 to 20 months (another personal experience)
Your friend will have to submit the application from here to seek approval. Normally CIC will have to see your friend's financial status, to determine the approval. After everything is settle from the Canada side, then his fiance can apply from China, and the Embassy of Canada will ask her to provide some documents to support the application. I don't recommend to seek help from the immigration services, because CIC can't refuse this type of application, unless you are member of the terrorist group etc. This type of application involves less technical twists as indepandent immigration does.
If he gets her here as a visitor status, then apply for the landing immigration. CIC will treat it with different approach, and sometimes you will have to provide the documents that can only be produced from China, which could be a hassle, and delay the whole process time as well.