javascript querystring function

gistfile1.js

function querystring(param) {
    if (location.search.length > 1) {
        var qsArgs = location.search.substring(1, location.search.length).replace(/\+/g, " ").split("&");
        for (var i = 0; i < qsArgs.length; i++) {
            var pair = qsArgs[i].split("=");
            var key = decodeURIComponent(pair[0]);
            if (param == key) {
                var value = (pair.length === 2)? decodeURIComponent(pair[1]): key;
                return value;
            }
        }
    }
};