We　study　the　entanglement　of　the　superconducting　charge　qubit　with　the　quantized　electromagnetic　field　in　a　microwave　cavity.　It　can　be　controlled　dynamically　by　a　classical　external　field　threading　the　SQUID　within　the　charge　qubit.　Utilizing　the　controllable　quantum　entanglement,　we　can　demonstrate　the　dynamic　process　of　the　quantum　storage　of　information　carried　by　charge　qubit.　On　the　other　hand,　based　on　this　engineered　quantum　entanglement,　we　can　also　demonstrate　a　progressive　decoherence　of　charge　cubit　with　quantum　jump　due　to　the　coupling　with　the　cavity　field　in　quasi-classical　state.