source: Dev/trunk/src/client/dojox/form/uploader/_IFrame.js

define([
        "dojo/query",
        "dojo/dom-construct",
        "dojo/_base/declare",
        "dojo/_base/lang",
        "dojo/_base/array",
        "dojo/dom-form",
        "dojo/request/iframe"
],function(query, domConstruct, declare, lang, arrayUtil, domForm, request){
        

        return declare("dojox.form.uploader._IFrame", [], {
                // summary:
                //              A mixin for dojox/form/Uploader that adds Ajax upload capabilities via an iframe.
                //
                // description:
                //              Only supported by IE, due to the specific iFrame hack used.  Progress events are not
                //              supported.
                //              
                //
        
                postMixInProperties: function(){
                        this.inherited(arguments);
                        if(this.uploadType === "iframe"){
                                this.uploadType = "iframe";
                                this.upload = this.uploadIFrame;
                        }
                },
        
                uploadIFrame: function(data){
                        // summary:
                        //              Internal. You could use this, but you should use upload() or submit();
                        //              which can also handle the post data.
        
                        var
                                formObject = {},
                                sendForm,
                                form = this.getForm(),
                                url = this.getUrl(),
                                self = this;
                        data = data || {};
                        data.uploadType = this.uploadType;
                        
                        // create a temp form for which to send data
                        //enctype can't be changed once a form element is created
                        sendForm = domConstruct.place('<form enctype="multipart/form-data" method="post"></form>', this.domNode);
                        arrayUtil.forEach(this._inputs, function(n, i){
                                // don't send blank inputs
                                if(n.value !== ''){
                                        sendForm.appendChild(n);
                                        formObject[n.name] = n.value;
                                }
                        }, this);
                        
                        
                        // add any extra data as form inputs            
                        if(data){
                                //formObject = domForm.toObject(form);
                                for(nm in data){
                                        if(formObject[nm] === undefined){
                                                domConstruct.create('input', {name:nm, value:data[nm], type:'hidden'}, sendForm);
                                        }
                                }
                        }
        
                        
                        request.post(url, {
                                form: sendForm,
                                handleAs: "json",
                                content: data
                        }).then(function(result){
                                domConstruct.destroy(sendForm);
                                if(result["ERROR"] || result["error"]){
                                        self.onError(result);
                                }else{
                                        self.onComplete(result);
                                }
                        }, function(err){
                                console.error('error parsing server result', err);
                                domConstruct.destroy(sendForm); 
                                self.onError(err);
                        });
                }
        });
});