form.js

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/*
 * jQuery form plugin
 * @requires jQuery v1.0.3
 *
 * Dual licensed under the MIT and GPL licenses:
 *   http://www.opensource.org/licenses/mit-license.php
 *   http://www.gnu.org/licenses/gpl.html
 *
 * Revision: $Id$
 * Version: .97
 */

/**
 * ajaxSubmit() provides a mechanism for submitting an HTML form using AJAX.
 *
 * ajaxSubmit accepts a single argument which can be either a success callback function
 * or an options Object.  If a function is provided it will be invoked upon successful
 * completion of the submit and will be passed the response from the server.
 * If an options Object is provided, the following attributes are supported:
 *
 *  target:   Identifies the element(s) in the page to be updated with the server response.
 *            This value may be specified as a jQuery selection string, a jQuery object,
 *            or a DOM element.
 *            default value: null
 *
 *  url:      URL to which the form data will be submitted.
 *            default value: value of form's 'action' attribute
 *
 *  type:     The method in which the form data should be submitted, 'GET' or 'POST'.
 *            default value: value of form's 'method' attribute (or 'GET' if none found)
 *
 *  beforeSubmit:  Callback method to be invoked before the form is submitted.
 *            default value: null
 *
 *  success:  Callback method to be invoked after the form has been successfully submitted
 *            and the response has been returned from the server
 *            default value: null
 *
 *  dataType: Expected dataType of the response.  One of: null, 'xml', 'script', or 'json'
 *            default value: null
 *
 *  semantic: Boolean flag indicating whether data must be submitted in semantic order (slower).
 *            default value: false
 *
 *  resetForm: Boolean flag indicating whether the form should be reset if the submit is successful
 *
 *  clearForm: Boolean flag indicating whether the form should be cleared if the submit is successful
 *
 *
 * The 'beforeSubmit' callback can be provided as a hook for running pre-submit logic or for
 * validating the form data.  If the 'beforeSubmit' callback returns false then the form will
 * not be submitted. The 'beforeSubmit' callback is invoked with three arguments: the form data
 * in array format, the jQuery object, and the options object passed into ajaxSubmit.
 * The form data array takes the following form:
 *
 *     [ { name: 'username', value: 'jresig' }, { name: 'password', value: 'secret' } ]
 *
 * If a 'success' callback method is provided it is invoked after the response has been returned
 * from the server.  It is passed the responseText or responseXML value (depending on dataType).
 * See jQuery.ajax for further details.
 *
 *
 * The dataType option provides a means for specifying how the server response should be handled.
 * This maps directly to the jQuery.httpData method.  The following values are supported:
 *
 *      'xml':    if dataType == 'xml' the server response is treated as XML and the 'after'
 *                   callback method, if specified, will be passed the responseXML value
 *      'json':   if dataType == 'json' the server response will be evaluted and passed to
 *                   the 'after' callback, if specified
 *      'script': if dataType == 'script' the server response is evaluated in the global context
 *
 *
 * Note that it does not make sense to use both the 'target' and 'dataType' options.  If both
 * are provided the target will be ignored.
 *
 * The semantic argument can be used to force form serialization in semantic order.
 * This is normally true anyway, unless the form contains input elements of type='image'.
 * If your form must be submitted with name/value pairs in semantic order and your form
 * contains an input of type='image" then pass true for this arg, otherwise pass false
 * (or nothing) to avoid the overhead for this logic.
 *
 *
 * When used on its own, ajaxSubmit() is typically bound to a form's submit event like this:
 *
 * $("#form-id").submit(function() {
 *     $(this).ajaxSubmit(options);
 *     return false; // cancel conventional submit
 * });
 *
 * When using ajaxForm(), however, this is done for you.
 *
 * @example
 * $('#myForm').ajaxSubmit(function(data) {
 *     alert('Form submit succeeded! Server returned: ' + data);
 * });
 * @desc Submit form and alert server response
 *
 *
 * @example
 * var options = {
 *     target: '#myTargetDiv'
 * };
 * $('#myForm').ajaxSubmit(options);
 * @desc Submit form and update page element with server response
 *
 *
 * @example
 * var options = {
 *     success: function(responseText) {
 *         alert(responseText);
 *     }
 * };
 * $('#myForm').ajaxSubmit(options);
 * @desc Submit form and alert the server response
 *
 *
 * @example
 * var options = {
 *     beforeSubmit: function(formArray, jqForm) {
 *         if (formArray.length == 0) {
 *             alert('Please enter data.');
 *             return false;
 *         }
 *     }
 * };
 * $('#myForm').ajaxSubmit(options);
 * @desc Pre-submit validation which aborts the submit operation if form data is empty
 *
 *
 * @example
 * var options = {
 *     url: myJsonUrl.php,
 *     dataType: 'json',
 *     success: function(data) {
 *        // 'data' is an object representing the the evaluated json data
 *     }
 * };
 * $('#myForm').ajaxSubmit(options);
 * @desc json data returned and evaluated
 *
 *
 * @example
 * var options = {
 *     url: myXmlUrl.php,
 *     dataType: 'xml',
 *     success: function(responseXML) {
 *        // responseXML is XML document object
 *        var data = $('myElement', responseXML).text();
 *     }
 * };
 * $('#myForm').ajaxSubmit(options);
 * @desc XML data returned from server
 *
 *
 * @example
 * var options = {
 *     resetForm: true
 * };
 * $('#myForm').ajaxSubmit(options);
 * @desc submit form and reset it if successful
 *
 * @example
 * $('#myForm).submit(function() {
 *    $(this).ajaxSubmit();
 *    return false;
 * });
 * @desc Bind form's submit event to use ajaxSubmit
 *
 *
 * @name ajaxSubmit
 * @type jQuery
 * @param options  object literal containing options which control the form submission process
 * @cat Plugins/Form
 * @return jQuery
 * @see formToArray
 * @see ajaxForm
 * @see $.ajax
 * @author jQuery Community
 */
jQuery.fn.ajaxSubmit = function(options) {
    if (typeof options == 'function')
        options = { success: options };

    options = jQuery.extend({
        url:  this.attr('action') || window.location,
        type: this.attr('method') || 'GET'
    }, options || {});

    var a = this.formToArray(options.semantic);

    // give pre-submit callback an opportunity to abort the submit
    if (options.beforeSubmit && options.beforeSubmit(a, this, options) === false) return this;

    // fire vetoable 'validate' event
    var veto = {};
    jQuery.event.trigger('form.submit.validate', [a, this, options, veto]);
    if (veto.veto)
        return this;

    var q = jQuery.param(a);//.replace(/%20/g,'+');

    if (options.type.toUpperCase() == 'GET') {
        options.url += (options.url.indexOf('?') >= 0 ? '&' : '?') + q;
        options.data = null;  // data is null for 'get'
    }
    else
        options.data = q; // data is the query string for 'post'

    var $form = this, callbacks = [];
    if (options.resetForm) callbacks.push(function() { $form.resetForm(); });
    if (options.clearForm) callbacks.push(function() { $form.clearForm(); });

    // perform a load on the target only if dataType is not provided
    if (!options.dataType && options.target) {
        var oldSuccess = options.success || function(){};
        callbacks.push(function(data, status) {
            jQuery(options.target).attr("innerHTML", data).evalScripts().each(oldSuccess, [data, status]);
        });
    }
    else if (options.success)
        callbacks.push(options.success);

    options.success = function(data, status) {
        for (var i=0, max=callbacks.length; i < max; i++)
            callbacks[i](data, status);
    };

    // are there files to upload?
    var files = jQuery('input:file', this).fieldValue();
    var found = false;
    for (var j=0; j < files.length; j++)
        if (files[j]) 
            found = true;

    if (options.iframe || found) // options.iframe allows user to force iframe mode
        fileUpload();
    else
        jQuery.ajax(options);

    // fire 'notify' event
    jQuery.event.trigger('form.submit.notify', [this, options]);
    return this;


    // private function for handling file uploads (hat tip to YAHOO!)
    function fileUpload() {
        var form = $form[0];
        var opts = jQuery.extend({}, jQuery.ajaxSettings, options);
        
        var id = 'jqFormIO' + jQuery.fn.ajaxSubmit.counter++;
        var $io = jQuery('<iframe id="' + id + '" name="' + id + '" />');
        var io = $io[0];
        var op8 = jQuery.browser.opera && window.opera.version() < 9;
        if (jQuery.browser.msie || op8) io.src = 'javascript:false;document.write("");';
        $io.css({ position: 'absolute', top: '-1000px', left: '-1000px' });

        // make sure form attrs are set
        form.method = 'POST';
        form.encoding ? form.encoding = 'multipart/form-data' : form.enctype = 'multipart/form-data';

        var xhr = { // mock object
            responseText: null,
            responseXML: null,
            status: 0,
            statusText: 'n/a',
            getAllResponseHeaders: function() {},
            getResponseHeader: function() {},
            setRequestHeader: function() {}
        };
        
        var g = opts.global;
        // trigger ajax global events so that activity/block indicators work like normal
        if (g && ! jQuery.active++) jQuery.event.trigger("ajaxStart");
        if (g) jQuery.event.trigger("ajaxSend", [xhr, opts]);
        
        var cbInvoked = 0;
        var timedOut = 0;
        
        // take a breath so that pending repaints get some cpu time before the upload starts
        setTimeout(function() {
            $io.appendTo('body');
            // jQuery's event binding doesn't work for iframe events in IE
            io.attachEvent ? io.attachEvent('onload', cb) : io.addEventListener('load', cb, false);
            form.action = opts.url;
            var t = form.target;
            form.target = id;

            // support timout
            if (opts.timeout)
                setTimeout(function() { timedOut = true; cb(); }, opts.timeout);

            form.submit();
            form.target = t; // reset
        }, 10);
        
        function cb() {
            if (cbInvoked++) return;
            
            io.detachEvent ? io.detachEvent('onload', cb) : io.removeEventListener('load', cb, false);

            var ok = true;
            try {
                if (timedOut) throw 'timeout';
                // extract the server response from the iframe
                var data, doc;
                doc = io.contentWindow ? io.contentWindow.document : io.contentDocument ? io.contentDocument : io.document;
                xhr.responseText = doc.body ? doc.body.innerHTML : null;
                xhr.responseXML = doc.XMLDocument ? doc.XMLDocument : doc;
                
                if (opts.dataType == 'json' || opts.dataType == 'script') {
                    var ta = doc.getElementsByTagName('textarea')[0];
                    data = ta ? ta.value : xhr.responseText;
                    if (opts.dataType == 'json')
                        eval("data = " + data);
                    else
                        jQuery.globalEval(data);
                }
                else if (opts.dataType == 'xml') {
                    data = xhr.responseXML;
                    if (!data && xhr.responseText != null)
                        data = toXml(xhr.responseText);
                }
                else {
                    data = xhr.responseText;
                }
            }
            catch(e){
                ok = false;
                jQuery.handleError(opts, xhr, 'error', e);
            }

            // ordering of these callbacks/triggers is odd, but that's how $.ajax does it
            if (ok) {
                opts.success(data, 'success');
                if (g) jQuery.event.trigger("ajaxSuccess", [xhr, opts]);
            }
            if (g) jQuery.event.trigger("ajaxComplete", [xhr, opts]);
            if (g && ! --jQuery.active) jQuery.event.trigger("ajaxStop");
            if (opts.complete) opts.complete(xhr, ok ? 'success' : 'error');

            // clean up
            setTimeout(function() { 
                $io.remove(); 
                xhr.responseXML = null;
            }, 100);
        };
        
        function toXml(s, doc) {
            if (window.ActiveXObject) {
                doc = new ActiveXObject('Microsoft.XMLDOM');
                doc.async = 'false';
                doc.loadXML(s);
            }
            else
                doc = (new DOMParser()).parseFromString(s, 'text/xml');
            return (doc && doc.documentElement && doc.documentElement.tagName != 'parsererror') ? doc : null;
        }
    };
};
jQuery.fn.ajaxSubmit.counter = 0; // used to create unique iframe ids

/**
 * ajaxForm() provides a mechanism for fully automating form submission.
 *
 * The advantages of using this method instead of ajaxSubmit() are:
 *
 * 1: This method will include coordinates for <input type="image" /> elements (if the element
 *    is used to submit the form).
 * 2. This method will include the submit element's name/value data (for the element that was
 *    used to submit the form).
 * 3. This method binds the submit() method to the form for you.
 *
 * Note that for accurate x/y coordinates of image submit elements in all browsers
 * you need to also use the "dimensions" plugin (this method will auto-detect its presence).
 *
 * The options argument for ajaxForm works exactly as it does for ajaxSubmit.  ajaxForm merely
 * passes the options argument along after properly binding events for submit elements and
 * the form itself.  See ajaxSubmit for a full description of the options argument.
 *
 *
 * @example
 * var options = {
 *     target: '#myTargetDiv'
 * };
 * $('#myForm').ajaxSForm(options);
 * @desc Bind form's submit event so that 'myTargetDiv' is updated with the server response
 *       when the form is submitted.
 *
 *
 * @example
 * var options = {
 *     success: function(responseText) {
 *         alert(responseText);
 *     }
 * };