Question

I have a js string…

var string = "Hi how are you <b>today</b>";

I now have a new js string…

var newstring = "are today";

I want to remove all the words from var string that don’t match var newstring. I would also like to keep the tags that are associated with those words, if any.

Example Result:
are <b>today</b> 

Answer 1

There are some simpe ways to do something like this, if they will work for you depends on what you intend to use this for, but something like this maybe:

var string = "Hi how are you <b>today</b>",
    newstring = "are today",
    words = newstring.split(' ');

for (var i=0; i<words.length; i++) {
    var reg = new RegExp(words[i], 'gi');
    string = string.replace(reg, '');
}

console.log(string);​

FIDDLE