如何从Python中的字符串开头删除特殊字符

Question

I am getting my data from XML which may some time contain special Character at beginning like:

'This is a sample title or %&*I don't know if this is the text

I tried with : title[0].isstring() or title[0].isdigit() and then remove the character. But if there are more than one special character at the beginning, then how do I remove it? Do I need a for loop?

Answer 1

You could use a regular expression:

import re
mystring = re.sub(r"^\W+", "", mystring)

This removes all non-alphanumeric characters from the start of your string:

Explanation:

^   # Start of string
\W+ # One or more non-alphanumeric characters

Answer 2

>>> import re
>>> re.sub(r'^\W*', '', "%&*I don't know if this is the text")
"I don't know if this is the text"

#or

>>> "%&*I don't know if this is the text".lstrip("!@#$%^&*()")
"I don't know if this is the text"

Answer 3

If there are just a few specific kinds of characters you want to remove, use lstrip() ("left strip").

For instance, if you wanted to remove any starting % , & , or * characters, you'd use:

actual_title = title.lstrip("%&*")

On the other hand, if you want to remove any characters that aren't part of a certain set (eg alphanumerics), then the regex solution specified in Tim Pietzcker's solution is probably the easiest way.

Answer 4

Using a strip function to remove any special characters from the beginning and end of the string. Ex.

 str = ").* this is text .(" str.strip(")(.* ") Output: 'this is text' 

If you want to remove from the beginning of string use lstrip() Ex.

 str = ").* this is text .(" str.lstrip(")(.* ") Output: 'this is text .(' 

If you want to remove from the end of the string use rstrip() Ex.

 str = ").* this is text .(" str.rstrip(")(.* ") Output: ').* this is text'