  We investigate observational signatures of explosive chromospheric
evaporation during a white-light flare (WLF) that occurred on 2022 August 27.
Using the moment analysis, bisector techniques, and the Gaussian fitting
method, red-shifted velocities of less than 20 km/s are detected in
low-temperature spectral lines of Ha, C I and Si IV at the conjugated flare
kernels, which could be regarded as downflows caused by chromospheric
condensation. Blue-shifted velocities of about 30-40 km/s are found in the
high-temperature line of Fe XXI, which can be interpreted as upflows driven by
chromospheric evaporation. A nonthermal hard X-ray (HXR) source is co-spatial
with one of the flare kernels, and the Doppler velocities are temporally
correlated with the HXR fluxes. The nonthermal energy flux is estimated to be
at least (1.3+-0.2)*10^10 erg/s/cm^2. The radiation enhancement at Fe I 6569.2
A and 6173 A suggests that the flare is a WLF. Moreover, the while-light
emission at Fe I 6569.2 A is temporally and spatially correlated with the blue
shift of Fe XXI line, suggesting that both the white-light enhancement and the
chromospheric evaporation are triggered and driven by nonthermal electrons. All
our observations support the scenario of an electron-driven explosive
chromospheric evaporation in the WLF.
