Valid. If you want to resign, you only need to submit a resignation letter in writing to the employer's labor and personnel department 30 days in advance [Remember: require the employer to sign your name and date on your "Labor Delivery and Handover (Documents, Materials) Signature Form" ), the consent of the employer is not required. If you continue to work for 30 days, you can stop working on the 31st day. You have the right to ask the employer to go through the resignation procedures, and the employer should handle it (Article 31 of the Labor Law), and at the same time pay the salary in one lump sum (Salary Article 9 of the "Interim Provisions on Payment") and issue you a resignation certificate (Article 50 of the "Labor Contract Law"), otherwise the employer will violate the law.