Was there any examples of ancient/medieval armies having a code of conduct that prohibited violence against civilians?

The tenets of Dharmayuddha- more or less followed by most Bharata States throughout history- prohibit the following.

1- Murder of Civilians- especially women, children, the elderly, and brahmins.

2- Destruction of Agricultural lands and orchards, and unpaid acquisition of farmers' crops.

3- The slaughter of animals, especially Kine, and the pollution of Water Bodies.

4- The annihilation of Cities, Guilds, and Dams- and the desecration of Vigrahas.

5- Extinction of recognized family lines as well as torture and execution of prisoners.

Early Iron Age laws also do not recognise ambushes, hitting below the navel, night attacks, usage of poisonous gases in sieges, mercenaries, and other such tenets. However these had mostly been either rejected or being openly ignored by Classical times.