valid property
Implementation
static final RegExp valid = RegExp(r'^(?<fmday>0[1-9]|[12][0-9]|3[01])'
r'(?<fmhour>[0-1]\d|2[0-3])/'
r'(?<tlday>0[1-9]|[12][0-9]|3[01])'
r'(?<tlhour>[0-1]\d|2[0-4])$');
valid property
static final RegExp valid = RegExp(r'^(?<fmday>0[1-9]|[12][0-9]|3[01])'
r'(?<fmhour>[0-1]\d|2[0-3])/'
r'(?<tlday>0[1-9]|[12][0-9]|3[01])'
r'(?<tlhour>[0-1]\d|2[0-4])$');