  Gamma-ray bursts (GRBs) can be divided into three subclasses: X-ray flash
(XRF), X-ray rich (XRR), and classical GRB (C-GRB). An X-ray flare is the
rebrightening emission shown in the early X-ray afterglow of some GRBs. In this
paper, we comprehensively examine the X-ray flare properties among XRF, XRR,
and C-GRB subclasses. We utilize the XRF, XRR, and C-GRB subclass samples
obtained from the Swift-BAT3 catalog, and the X-ray flare observational
properties are collected from Falcone et al., Chincarini et al., and Yi et al.
We find that XRFs and XRRs have more bright X-ray flares than C-GRBs. The ratio
of the X-ray flare fluence to the prompt emission fluence has different
distributions between XRF and C-GRB subclasses. The linear correlation between
the duration and the peak time of the X-ray flares is also different between
XRF and C-GRB subclasses. We are inclined to identify the GRBs with the bright
X-ray flares as XRFs or XRRs. We discuss some issues that are related to the
XRF/XRR/C-GRB classification. We also caution the selection effects and the
instrument bias in our investigation. Large samples are required in the future
to further confirm our results.
