javascript regex multiple condition

Question

I have a html entities replacement for & that look like this:

function htmlEntities(str) {
return String(str).replace(/&(?!amp;)/g, '&');
}

which are working fine that not to replace the & but will replace &

how do I add multiple condition to regex of my function so that it will not mess with other html entities like:

'
"
>
<

i test with:

var xxx = "1234 &aaa&amp; aaadas 'xxx' \" kkk <aasd> xxxxxxxxxxxxxxxx &lt;";

console.log(htmlEntities(xxx));

it will replace the < to become < and this is not what I want, i need it to leave the < untouch just like the example &aaa& to become &aaa&

hope you get what I mean, any idea?

Answer 1

You can use | in a regexp to make alternatives.

var xxx = "1234 &aaa&amp; aaadas 'xxx' \" kkk <aasd> xxxxxxxxxxxxxxxx &lt;";
console.log(htmlEntities(xxx));

function htmlEntities(str) {
  return String(str).replace(/&(?!(?:amp|apos|gt|lt);)/g, '&amp;');
}