python validate string allowed only spaces, alphabet and numbers

Using pattern matching, this is not hard to achieve.

To check that each character matches your requirements

Regular expression

"^[a-zA-Z0-9_]*$"

With spaces checking:

"^[a-zA-Z0-9_ ]*$"

Code example:


if allow_special_char == False:
import re
if not re.match("^[a-zA-Z0-9_ ]*$", gname):
print "Invalid"


Regular expression refer from http://stackoverflow.com/a/336220/1903116

reference: http://stackoverflow.com/questions/19970532/how-to-check-a-string-for-a-special-character

By Keenlio, September 29, 2015