jQuery file upload上传图片出错分析

以https://github.com/blueimp/jQuery-File-Upload/blob/master/basic-plus.html为例

注释掉load-image.all.min.js

<!--script src="//blueimp.github.io/JavaScript-Load-Image/js/load-image.all.min.js"></script-->

jquery.fileupload-image.js:279 Uncaught TypeError: Cannot read property 'parseMetaData' of undefined
at $.<computed>.<computed>.loadImageMetaData (jquery.fileupload-image.js:279)
at $.<computed>.<computed>.func (jquery.fileupload-process.js:84)
at $.<computed>.<computed>.<anonymous> (jquery.js:3305)
at fire (jquery.js:3148)
at Object.add [as done] (jquery.js:3194)
at Array.<anonymous> (jquery.js:3304)
at Function.each (jquery.js:384)
at Object.<anonymous> (jquery.js:3301)
at Function.Deferred (jquery.js:3361)
at Object.then (jquery.js:3300)

jquery.fileupload-process.js:84

_processFile: function (data, originalData) {这个函数中

return that.processActions[settings.action].call(
    that,
    data,
    settings
);

jquery.fileupload-process.js:153

_processFile函数，被process函数调用

// Processes the files given as files property of the data parameter,
// returns a Promise object that allows to bind callbacks:
process: function (data) {

$.each(data.files, function (index) {
    var opts = index ? $.extend({}, options) : options,
        func = function () {
            if (data.errorThrown) {
                return $.Deferred()
                        .rejectWith(that, [data]).promise();
            }
            return that._processFile(opts, data);
        };

jquery.fileupload.js:217

// The add callback is invoked as soon as files are added to the fileupload
// widget (via file input selection, drag & drop, paste or add API call).
// If the singleFileUploads option is enabled, this callback will be
// called once for each file in the selection for XHR file uploads, else
// once for each file selection.
//
// The upload starts when the submit method is invoked on the data parameter.
// The data object contains a files property holding the added files
// and allows you to override plugin options as well as define ajax settings.
//
// Listeners for this callback can also be bound the following way:
// .bind('fileuploadadd', func);
//
// data.submit() returns a Promise object and allows to attach additional
// handlers using jQuery's Deferred callbacks:
// data.submit().done(func).fail(func).always(func);
add: function (e, data) {
    if (e.isDefaultPrevented()) {
        return false;
    }
    if (data.autoUpload || (data.autoUpload !== false &&
            $(this).fileupload('option', 'autoUpload'))) {
        data.process().done(function () {
            data.submit();
        });
    }
},