A consensus is reached and the signatures of both parties are valid. Written evidence is a form for citizens and legal persons to carry out civil legal acts.

Details are as follows:

1. The parties may conclude the contract in written form, orally or in other forms;

2. Written forms are contracts, letters, telegrams, telexes, faxes and other forms that can tangibly express the contents contained;

3, electronic data exchange, e-mail, etc. If the content can be expressed tangibly and the data message can be retrieved for reference at any time, it shall be regarded as a written form.

A valid contract must meet the following requirements:

1, the contract subject must have the specified capacity for civil conduct; Secondly, meaning is truth;

2. The contents of the contract do not violate the law or public interests. Therefore, as long as the above conditions are met, the agreement signed by both parties has legal effect;

3. If it belongs to a special type of contract, such as a practice contract or a loan contract. The contract can only be established after both parties sign it, but it will only take effect after the lender delivers the lent money to the borrower. Therefore, the contract signed by both parties takes effect.

Contact between the effectiveness of the contract and the establishment of the contract:

1, most contracts take effect immediately, that is, contracts are established at the same time when they take effect;

2. The contract does not take effect immediately after it is established, but only after the approval and registration procedures are completed.

3. The contract does not take effect immediately after it is established, and the effective time depends on when the attached period comes, that is, the contract with extended period;

4. The contract does not take effect immediately after it is established. Whether it can take effect depends on whether the attached conditions can be realized, that is, the contract with extension conditions;

5. After the contract is established, its validity is suspended. Whether the contract can come into effect depends on whether the effective elements lacking at the time of the establishment of the contract can be corrected afterwards, that is, the contract with undetermined effect;

6. After the contract is established, it will never take effect, that is, the contract is invalid;

7. If the laws and administrative regulations clearly stipulate that a certain type of contract should be approved and registered before it takes effect, then the approval and registration procedures at this time are the effective elements of the contract. If it is not handled, the people's court shall determine that the contract has not come into effect. However, it should be noted that as long as the approval and registration procedures are completed before the end of the debate in the court of first instance, the people's court shall consider the contract valid.

To sum up, civil juristic acts can be written, oral or other forms. However, in civil activities, written civil juristic acts are generally the main form, because this can objectively and effectively record the rights and obligations of the parties involved in civil juristic acts or the objective facts to be reflected in civil juristic acts. Thereby effectively safeguarding the legitimate rights and interests of all parties.

Legal basis:

Article 502 of the Civil Code of People's Republic of China (PRC)

A legally established contract shall come into force upon its establishment, except as otherwise provided by law or agreed by the parties.

In accordance with the provisions of laws and administrative regulations, if the contract should go through the approval procedures, such provisions shall prevail. If the failure to go through the formalities such as approval affects the effectiveness of the contract, it will not affect the performance of the obligation clauses such as approval and the effectiveness of relevant clauses in the contract. If the party that should go through the formalities for approval fails to perform its obligations, the other party may require it to bear the responsibility for violating its obligations.

The modification, assignment and dissolution of a contract shall be subject to the provisions of laws and administrative regulations, and the provisions of the preceding paragraph shall apply and shall be subject to approval.