  During the inspiralling of a white dwarf (WD) into an intermediate-mass black
hole (~ 10^{2-5} M_sun), both gravitational waves (GWs) and electromagnetic
(EM) radiation are emitted. Once the eccentric orbit's pericenter radius
approaches the tidal radius, the WD would be tidally stripped upon each
pericenter passage. The accretion of these stripped mass would produce EM
radiation. It is suspected that the recently discovered new types of
transients, namely the quasi-periodic eruptions and the fast ultraluminous
X-ray bursts, might originate from such systems. Modeling these flares requires
a prediction of the amount of stripped mass from the WD and the details of the
mass supply to the accretion disk. We run hydrodynamical simulations to study
the orbital parameter dependence of the stripped mass. We find that our results
match the analytical estimate that the stripped mass is proportional to
z^{5/2}, where z is the excess depth by which the WD overfills its
instantaneous Roche lobe at the pericenter. The corresponding fallback rate of
the stripped mass is calculated, which may be useful in interpreting the
individual flaring light curve in candidate EM sources. We further calculate
the long-term mass-loss evolution of a WD during its inspiral and the
detectability of the GW and EM signals. The EM signal from the mass-loss stage
can be easily detected: the limiting distance is ~ 320(M_h/10^4 M_sun)^{1/2}
Mpc for Einstein Probe. The GW signal, for the space-borne detectors such as
Laser Interferometer Space Antenna or TianQin, can be detected only within the
Local Supercluster (~ 33 Mpc).
