How to create a regex in Python to detect illegal characters, including double-quotes?-CodePudding

I'm creating a python script that basically creates directory structures on Windows. The names of these directories (or folders) come from user input. I want to make sure that they're not entering characters that will cause a failure when trying to create these directories.

The chars I'm trying to filter so far include: <, >, :, ", /, \, |, ?, * I think that's all of them.

But when creating the regex using the re module, it gets rather confusing because you need to compile a string:

pattern = re.compile(r'!["\/:|<>*?]')

and then when I enter something like: Foo:?

result = re.search(pattern, input_text)

The result is None. Why isn't it finding any of the the illegal chars? Admittingly, I'm new to Python and haven't used regex all that much.

CodePudding user response：

The temptation to use regex is big, but I would rather go for a non regex solution

illegal_chars = r'<>:"/\|?*'
dir_name = input("Enter dir_name: ")
for c in illegal_chars:
    if c in dir_name:
        print("ERR - illegal character '{}'".format(c))
        exit(111)
print("Name '{}' is OK for a dir".format(dir_name))

CodePudding user response：

Ok, I got this working with:

input_str = "Foo:"
pattern = re.compile(r'["\/:|<>*?]')
result = re.search(pattern, input_str)
# found ":"

This will return a match if any one of those characters are found in the string.

CodePudding user response：

invalid character for a windows directory are:

.
\\
/
:
*
?
"
<
>
|