``` getObjectURL(file) { var url = null; if(window.createObjectURL != undefined) { // basic url = window.createObjectURL(file); } else if(window.URL != undefined) { // mozilla(firefox) url = window.URL.createObjectURL(file); } else if(window.webkitURL != undefined) { // webkit or chrome url = window.webkitURL.createObjectURL(file); } return url; }, ```