Clicks answers in a questionnaire based on queries in the URL.

q_answers_from_url.html

<script type="text/javascript">
    $(document).ready(function () {
        // SalsaStaff 88363: Click options in the checkbox/radio button
        // questions based on queries passed in the URL. The general form of
        // a query is `&Qm=n`, where `m` is the question number and `n` is
        // the answer number.  Both `m` and `n` are cardinal integers.
        //
        // @note This GIST contains guard logic to work on a single questoinnaire
        // because the script must go into a template.
        //
        if (/questionnaire_KEY=69/.test(window.location.href)) {
            // see http://stackoverflow.com/questions/901115/how-can-i-get-query-string-values-in-javascript
            function qs(key) {
                var vars = [], hash;
                var hashes = window.location.href.slice(window.location.href.indexOf('?') + 1).split('&');
                for(var i = 0; i < hashes.length; i++)
                {
                    hash = hashes[i].split('=');
                    vars.push(hash[0]);
                    vars[hash[0]] = hash[1];
                }
                return vars[key];
            }    

            var questions = {};
            $('.formRow fieldset').each (function(index, value) {
                var key = "Q" + (index + 1);
                questions[key] = [];
                $(this).find('input').each ( function(key2, value2) {
                    questions[key].push($(this).attr('id'));
                })
            });

            for (key in questions) {
                var arg = parseInt(qs(key)) || 0;
                if (arg < 1) {
                    console.log("Error! not a valid number, '" + qs(key) + "', for " + key + ".");
                }
                else {
                    var question = questions[key];
                    if (arg - 1 < question.length) {
                        var answer = question[arg - 1];
                        $('#' + answer).click();
                        console.log("Clicked #" + answer);
                    }
                    else {
                        console.log("Warning! " + key + " does not have an answer " + arg + ".");
                    }
                }
            }
        }
    });
</script>