  We reveal numerically and experimentally that dielectric resonance can
enhance the absorbance and emission of monolayer MoS$_2$. By quantifying the
absorbance of the Si disk resonators and the monolayer MoS$_2$ separately, a
model taking into account of absorbance as well as quantum efficiency
modifications by the dielectric disk resonators successfully explains the
observed emission enhancement under the normal light incidence. It is
demonstrated that the experimentally observed emission enhancement at different
pump wavelength results from the absorbance enhancement, which compensates the
emission quenching by the disk resonators. In order to further maximize the
absorbance value of monolayer MoS$_2$, a perfect absorbing structure is
proposed. By placing a Au mirror beneath the Si nanodisks, the incident
electromagnetic power is fully absorbed by the hybrid monolayer MoS$_2$-disk
system. It is demonstrated that the electromagnetic power is re-distributed
within the hybrid structure and 53\% of the total power is absorbed by the
monolayer MoS$_2$ at the perfect absorbing wavelength.
