How to deal with someone urinating in the corridor?

Corridor is a public area. If you urinate anywhere, it will worsen the environment and affect others. You can post a notice stating that it is forbidden to urinate here to warn others.

Alarm: According to Article 280 of the Civil Law of People's Republic of China (PRC), the decision of the owners' committee is legally binding on the owners, so defecation in the corridor of the residential area violates the regulations of the residential property and infringes on the rights and interests of others, so you can call the police.