checkdigit.py

python web programming 部分

#
# CheckDigit.py
#
def check(s):
    if len(s) != 6:
        raise TypeError
    if not s[5].isdigit():
        raise ValueError
    c = 0
    for digit, weight in zip(s[:5], [3, 5, 7, 11, 13]):
        if not digit.isdigit():
            raise ValueError
        c += int(digit) * weight
    if (c % 10) != int(s[5]):
        raise ValueError

try:
    while 1:
        try:
            s = raw_input("Part #: ")
            if s == "":
                break
            check(s)
            #
            # Here we would process the part
            #
            print "Part", s, "processed"
        except ValueError:
            print "Invalid check digit"
        except TypeError:
            print "Not a part number"
    print "\n\nProgram Terminated"
finally:
    print "\n\nThank you for your input"