validateGST static method

dynamic validateGST({
  1. required dynamic gst,
  2. required String fieldName,
})

Implementation

static dynamic validateGST(
    {required dynamic gst, required String fieldName}) {
  return gst == null || gst.toString().trim() == ''
      ? "Please Enter $fieldName"
      : !RegExp(r'^[0-9]{2}[A-Z]{5}[0-9]{4}[A-Z]{1}[1-9A-Z]{1}[Z]{1}[0-9A-Z]{1}$')
              .hasMatch(gst)
          ? "Please enter a valid $fieldName"
          : null;
}