Source: Tafsir al-Ahlam al-Kabir (Ibn Sirin)
The king in a dream is God Almighty. Seeing the king with a pleasant face indicates God's pleasure. His anger indicates God's anger. Whoever sees himself become a king will gain honor and nobility.
Source: Ta'tir al-Anam fi Ta'bir al-Manam (Al-Nabulsi)
The king indicates position and high status. Whoever sees himself talking to the king, his need will be fulfilled.
Source: Al-Isharat fi Ilm al-Ibarat (Ibn Shahin)
The king is interpreted as prestige and authority. Speaking with the king is fulfillment of a need. His death indicates the weakness of the state.