Filter

The invention provides a filter, and belongs to the technical field of water treatment devices. The filter comprises a shell, a multi-cavity filter element and a release electromagnetic valve. A water inlet and a water outlet are formed in the outer wall of the shell, and a mixing cavity and a cavity are formed in the shell. The multi-cavity filter element and the cavity form a water inlet flow channel, the water outlet end of the multi-cavity filter element is communicated with the mixing cavity, and the multi-cavity filter element filters tap water into purified water. The release solenoid valve is configured to close, open, close or communicate the central cavity so as to form two different purification paths with the multi-cavity filter element. The functions of filtering and releasing additives are achieved through the multi-cavity filter element, the filtering function is achieved through the filter elements with different filtering accuracies, and the problem that an existing pre-filter is single in fu