Regex Expression for special characters in Javascript

Question

I have the following regular expression

/[^a-zA-Z0-9 ]/g

I want include " in the following piece of code:

onKeyUp="this.value=this.value.replace(/[^a-zA-Z0-9"]/g,'')

I used the above regex.

The problem I am facing over here is that the above regular expression allows me to include other special characters ( & , * , etc.) into it. How do I avoid it?

Answer 1

Just put the characters into the character class while taking the correct encoding into account:

onKeyUp="this.value=this.value.replace(/[^a-zA-Z0-9"&*]/g,'')"

Here you need to encode " and & with the character references " and & as you're describing the value of an HTML attribute value declaration.

Answer 2

One first obvious issue with the code is that the " that is part of the regex isn't escaped despite it being inside a " -delimited string literal. You may want to try and change it to:

onKeyUp="this.value=this.value.replace(/[^a-zA-Z0-9\\" ]/g,'')