Legal basis: Civil Code of People's Republic of China (PRC).
Article 490 Where the parties conclude a contract in the form of a contract, the contract is formed when the parties sign, seal or fingerprint it. Before signing, sealing or fingerprinting, one party has fulfilled its main obligations, and the contract is established when the other party accepts it.
A contract shall be concluded in written form as stipulated by laws, administrative regulations or agreed by the parties. If the parties do not do this in writing, but one party has fulfilled its main obligations and the other party accepts it, the contract is established.
skill
The above answer is only for the current information combined with my understanding of the law, please refer carefully!
If you still have questions about this issue, I suggest you sort out relevant information and communicate with professionals in detail.