I wanted to write a javascript function to sanitize user input and remove any unwanted and dangerous characters.
It must allow only the following characters:
My first attempt was:
function sanitizeString(str){
str = str.replace(/[^a-z0-9áéíóúñü_-\s\.,]/gim,"");
return str.trim();
}
But if I did:
sanitizeString("word1\nword2")
it returns:
"word1
word2"
So I had to rewrite the function to remove explícitly \t\n\f\r\v\0:
function sanitizeString(str){
str = str.replace(/([^a-z0-9áéíóúñü_-\s\.,]|[\t\n\f\r\v\0])/gim,"");
return str.trim();
}
I'd like to know:
The new version of the sanitizeString function:
function sanitizeString(str){
str = str.replace(/[^a-z0-9áéíóúñü \.,_-]/gim,"");
return str.trim();
}
The main problem was mentioned by @RobG and @Derek: (@RobG write your comment as an answer and I will accept it) \s doesn't mean what now w3Schools says
Find a whitespace character
It means what MDN says
Matches a single white space character, including space, tab, form feed, line feed. Equivalent to [ \f\n\r\t\v\u00a0\u1680\u180e\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200a\u2028\u2029\u202f\u205f\u3000].
I trusted in w3Schools when I wrote the function.
A second change was to move the dash character (-) to the end in order to avoid it's range separator meaning.