jquery.form.js

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/*
 * jQuery Form Plugin
 * version: 2.12 (06/07/2008)
 * @requires jQuery v1.2.2 or later
 *
 * Examples and documentation at: http://malsup.com/jquery/form/
 * Dual licensed under the MIT and GPL licenses:
 *   http://www.opensource.org/licenses/mit-license.php
 *   http://www.gnu.org/licenses/gpl.html
 *
 * Revision: $Id$
 */
(function($) {

/*
    Usage Note:  
    -----------
    Do not use both ajaxSubmit and ajaxForm on the same form.  These
    functions are intended to be exclusive.  Use ajaxSubmit if you want
    to bind your own submit handler to the form.  For example,

    $(document).ready(function() {
        $('#myForm').bind('submit', function() {
            $(this).ajaxSubmit({
                target: '#output'
            });
            return false; // <-- important!
        });
    });

    Use ajaxForm when you want the plugin to manage all the event binding
    for you.  For example,

    $(document).ready(function() {
        $('#myForm').ajaxForm({
            target: '#output'
        });
    });
        
    When using ajaxForm, the ajaxSubmit function will be invoked for you
    at the appropriate time.  
*/

/**
 * ajaxSubmit() provides a mechanism for immediately submitting 
 * an HTML form using AJAX.
 */
$.fn.ajaxSubmit = function(options) {
    // fast fail if nothing selected (http://dev.jquery.com/ticket/2752)
    if (!this.length) {
        log('ajaxSubmit: skipping submit process - no element selected');
        return this;
    }

    if (typeof options == 'function')
        options = { success: options };

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

    // hook for manipulating the form data before it is extracted;
    // convenient for use with rich editors like tinyMCE or FCKEditor
    var veto = {};
    this.trigger('form-pre-serialize', [this, options, veto]);
    if (veto.veto) {
        log('ajaxSubmit: submit vetoed via form-pre-serialize trigger');
        return this;
   }

    var a = this.formToArray(options.semantic);
    if (options.data) {
        options.extraData = options.data;
        for (var n in options.data)
            a.push( { name: n, value: options.data[n] } );
    }

    // give pre-submit callback an opportunity to abort the submit
    if (options.beforeSubmit && options.beforeSubmit(a, this, options) === false) {
        log('ajaxSubmit: submit aborted via beforeSubmit callback');
        return this;
    }    

    // fire vetoable 'validate' event
    this.trigger('form-submit-validate', [a, this, options, veto]);
    if (veto.veto) {
        log('ajaxSubmit: submit vetoed via form-submit-validate trigger');
        return this;
    }    

    var q = $.param(a);

    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) {
            $(options.target).html(data).each(oldSuccess, arguments);
        });
    }
    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, $form);
    };

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

    // options.iframe allows user to force iframe mode
   if (options.iframe || found) { 
       // hack to fix Safari hang (thanks to Tim Molendijk for this)
       // see:  http://groups.google.com/group/jquery-dev/browse_thread/thread/36395b7ab510dd5d
       if ($.browser.safari && options.closeKeepAlive)
           $.get(options.closeKeepAlive, fileUpload);
       else
           fileUpload();
       }
   else
       $.ajax(options);

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


    // private function for handling file uploads (hat tip to YAHOO!)
    function fileUpload() {
        var form = $form[0];
        
        if ($(':input[@name=submit]', form).length) {
            alert('Error: Form elements must not be named "submit".');
            return;
        }
        
        var opts = $.extend({}, $.ajaxSettings, options);

        var id = 'jqFormIO' + (new Date().getTime());
        var $io = $('<iframe id="' + id + '" name="' + id + '" />');
        var io = $io[0];

        if ($.browser.msie || $.browser.opera) 
            io.src = 'javascript:false;document.write("");';
        $io.css({ position: 'absolute', top: '-1000px', left: '-1000px' });

        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 && ! $.active++) $.event.trigger("ajaxStart");
        if (g) $.event.trigger("ajaxSend", [xhr, opts]);

        var cbInvoked = 0;
        var timedOut = 0;

        // add submitting element to data if we know it
        var sub = form.clk;
        if (sub) {
            var n = sub.name;
            if (n && !sub.disabled) {
                options.extraData = options.extraData || {};
                options.extraData[n] = sub.value;
                if (sub.type == "image") {
                    options.extraData[name+'.x'] = form.clk_x;
                    options.extraData[name+'.y'] = form.clk_y;
                }
            }
        }
        
        // take a breath so that pending repaints get some cpu time before the upload starts
        setTimeout(function() {
            // make sure form attrs are set
            var t = $form.attr('target'), a = $form.attr('action');
            $form.attr({
                target:   id,
                encoding: 'multipart/form-data',
                enctype:  'multipart/form-data',
                method:   'POST',
                action:   opts.url
            });

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

            // add "extra" data to form if provided in options
            var extraInputs = [];
            try {
                if (options.extraData)
                    for (var n in options.extraData)
                        extraInputs.push(
                            $('<input type="hidden" name="'+n+'" value="'+options.extraData[n]+'" />')
                                .appendTo(form)[0]);
            
                // add iframe to doc and submit the form
                $io.appendTo('body');
                io.attachEvent ? io.attachEvent('onload', cb) : io.addEventListener('load', cb, false);
                form.submit();
            }
            finally {
                // reset attrs and remove "extra" input elements
                $form.attr('action', a);
                t ? $form.attr('target', t) : $form.removeAttr('target');
                $(extraInputs).remove();
            }
        }, 10);

        function cb() {
            if (cbInvoked++) return;
            
            io.detachEvent ? io.detachEvent('onload', cb) : io.removeEventListener('load', cb, false);

            var operaHack = 0;
            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;
                
                if (doc.body == null && !operaHack && $.browser.opera) {
                    // In Opera 9.2.x the iframe DOM is not always traversable when
                    // the onload callback fires so we give Opera 100ms to right itself
                    operaHack = 1;
                    cbInvoked--;
                    setTimeout(cb, 100);
                    return;
                }
                
                xhr.responseText = doc.body ? doc.body.innerHTML : null;
                xhr.responseXML = doc.XMLDocument ? doc.XMLDocument : doc;
                xhr.getResponseHeader = function(header){
                    var headers = {'content-type': opts.dataType};
                    return headers[header];
                };

                if (opts.dataType == 'json' || opts.dataType == 'script') {
                    var ta = doc.getElementsByTagName('textarea')[0];
                    xhr.responseText = ta ? ta.value : xhr.responseText;
                }
                else if (opts.dataType == 'xml' && !xhr.responseXML && xhr.responseText != null) {
                    xhr.responseXML = toXml(xhr.responseText);
                }
                data = $.httpData(xhr, opts.dataType);
            }
            catch(e){
                ok = false;
                $.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) $.event.trigger("ajaxSuccess", [xhr, opts]);
            }
            if (g) $.event.trigger("ajaxComplete", [xhr, opts]);
            if (g && ! --$.active) $.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;