Javascript Not Matching correct words for validation

This is a follow up to another post I put here

So I have a form and I dont want to accept certain words. However Say you Enter "Post" I dont want it to match "pos" so I have accomplished that part the script no longer matches parts just whole words but for some reason if I enter "Positive" it does not match "positive" with the word boundaries on the regex

 var resword = new Array("positive","pos","negative","neg","neutral", "neu","twitter","itunes","facebook","android","forums","RSS Feeds");

 var valueLen = $("#aname").val().length;
 var fail=false;

 var filterElem = $('#aname');
 var filterName = $('#aname').val();

            $.each(resword,function(){
                    if ( filterName.toLowerCase().match("\b"+this+"\b")) {
                            filterElem.css('border','2px solid red');
                            window.alert("You can not开发者_如何学Go include '" + this + "' in your Filter Name");
                            fail = true;
                    }
            });

I would suggest a bit cleaner way to implement this that takes all the words and puts them in one regular expression. This method also has a feature enhancement to do just one alert that shows all the illegal words. Here's the code which you can see working in this jsFiddle.

function check() {
    var resword = new Array("positive","pos","negative","neg","neutral", "neu","twitter","itunes","facebook","android","forums","RSS Feeds");

    // build one regex with all the words in it
    // assumes that the words themselves dont' have regex characgers in them
    var regex = new RegExp("\\b" + resword.join("\\b|\\b") + "\\b", "ig");
    var filterElem = $('#aname');
    var match, plural, errors = [];

    // call regex.exec until no more matches
    while ((match = regex.exec(filterElem.val())) != null) {
        errors.push(match[0]);   // accumulate each illegal word match
    }
    // if there were any errors, put them together and prompt the user
    if (errors.length > 0) {
        plural = errors.length > 1 ? "s" : "";
        filterElem.css('border','2px solid red');
        alert("You can not include the word" + plural + " '" + errors.join("' and '") + "' in your Filter Name");
    }
    return(errors.length == 0);   // return true if no errors, false if errors
}

You need to double escape your backslashes (\) since it's in a string:

.match("\\b"+this+"\\b")