Solar　heating　(SH)　and　radiative　cooling　(RC)　are　effective　methods　for　thermal　management　using　solar　energy　and　cold　outer　space,　respectively.　However,　effectively　integrating　SH　and　RC　to　meet　various　seasonal　demands　poses　a　challenge　due　to　the　differing　radiative　properties　needed　for　the　material　surfaces.　In　this　work,　we　propose　a　flexible　energy-saving　surface　(FESS)　with　the　coupling　effect　of　a　resonant　cavity　and　a　photonic　structure,　which　can　synergistically　control　both　near-infrared(NIR)　and　long-wave　infrared(LIR).　The　resonant　cavity　in　FESS　is　driven　by　a　metal-insulator　phase　transition　that　exhibits　different　emissivity　at　high　and　low　temperatures　to　regulate　RC　automatically.　Simultaneously,　the　photonic　structure　achieves　flexible　control　of　NIR　reflectivity　within　the　range　of　0.176-0.814　through　its　structure,　enabling　the　on-demand　modulation　of　the　SH.　As　a　result,　the　normal　building　integrating　the　FESS　can　cool　low　to　11.61　degrees　C　during　warm　weather　(35　degrees　C)　and　up　to　18.95　degrees　C　during　cold　weather　(0　degrees　C),　reducing　thermal　management　energy　consumption　by　6.4　%-　43.5　%　in　various　climatic　regions　worldwide.　The　presented　FESS　may　be　expected　to　be　widely　applied　to　the　external　surfaces　of　buildings,　vehicles,　or　other　shading　structures,　providing　assistance　for　cooling/heating　without　energy　consumption.