I guess that it is impossible for you to get a China visa in South Africa because you are a temporary visitors there. But you can have a try to apply for China visa, the requirements for China tourist visa are:
. One completely filled out Visa Application Form.
2. One recently taken 2X2 in. photo. Please stick the photo to the application form.
3. Original passport
4. Copy of air ticket and hotel booking.
5. updated bankstatement is required for first time visitors .