The fastest in Beijing and Guangzhou is Air Egypt, and Bangkok stops at 1 hour. The flight time is about 14 hour.
Shanghai can choose Qatar, United Arab Emirates and South Korea. (That's what people usually come here.) The flight time is about 14- 16 hours.
This line is:
Qatar Airways: Shanghai-Doha-Cairo
Emirates Airlines: Shanghai-Dubai-Cairo
Korea: Shanghai-Seoul-Dubai-Cairo
In terms of price, EgyptAir is the cheapest, followed by Qatar, United Arab Emirates and South Korea.