hex check

[Troels Therkelsen]

In article <mailman.1058340712.8247.python-list at python.org>, Ruslan Spivak wrote:
> Hello.
> 
> Does anybody have a hint how to check if input hex number is in correct 
> hex format?
> 
> Thanks in advance.

You could try the int() built-in function:

Python 2.3b2 (#1, Jun 30 2003, 13:04:39) 
[GCC 2.95.3 20010315 (release)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> int("f3", 16)
243
>>> int("0xf3", 16)
243
>>> int("f3g", 16)
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
ValueError: invalid literal for int(): f3g
>>> 

You'd have to wrap it in a construct like this, for example:

    inputhex = "f3"
    try:
        i = int(inputhex, 16)
    except ValueErr:
        print "Bad hex input: %s" % inputhex


Hope this hint helps,

Troels Therkelsen.