Air purifier

An air purifier comprising a main body, wherein the main body comprises:

• a housing, wherein an interior of the housing is hollow, end plates are fixed at two ends of the housing, a plurality of airflow holes are formed in the end plates, an air inlet is formed at one end of the housing, an air outlet is formed at the other end of the housing, and positions of the air inlet and the air outlet are interchangeable;
• a fan mounted in the housing and used for sucking outside air from one end of the housing or for sucking outside air from the other end of the housing;
• a photocatalyst member mounted in the housing;
• ultraviolet light-emitting members mounted in the housing, so that ultraviolet light emitted by the ultraviolet light-emitting members effectively irradiate the photocatalyst member.