Splitting a String by an Array of Words in Javascript

I'm taking some text and want to split it into an array. My goal is to be able to split it into phrases delimited by stopwords (words ignored by search engines, like 'a' 'the' etc), so that I can then search each individual phrase in my API. So for example: 'The cow's hat was really funny' would result in arr[0] = cow's hat and arr[1] = funny. I ha开发者_运维问答ve an array of stopwords already but I can't really think of how to actually split by each/any of the words in it, without writing a very slow function to loop through each one.

Use split(). It takes a regular expression. The following is a simple example:

search_string.split(/\b(?:a|the|was|\s)+\b/i);

If you already have the array of stop words, you could use join() to build the regular expression. Try the following:

regex = new RegExp("\\b(?:" + stop_words.join('|') + "|\\s)+\\b", "i");

A working example http://jsfiddle.net/NEnR8/. NOTE: it may be best to replace these values than to split on them as there are empty array elements from this result.

This does a case insensitive .split() on your keywords, surrounded by word boundries.

  var str = "The cow's hat was really funny";

  var arr = str.split(/\ba\b|\bthe\b|\bwas\b/i);

You may end up with some empty items in the Array. To compact it, you could do this:

  var len = arr.length;

  while( len-- ) {
    if( !arr[len] )
        arr.splice( len, 1);
  }

Quick and dirty way would be to replace the "stop word" strings with some unique characters (e.g. &&&), and then split based on that unique character.

For example.

var the_text = "..............",
    stop_words = ['foo', 'bar', 'etc'],
    unique_str = '&&&';

for (var i = 0; i < stop_words.length; i += 1) {
  the_text.replace(stop_words[i], unique_str);
}

the_text.split(unique_str);