Simple Ajax Uploader

A Javascript plugin for cross-browser Ajax file uploading. Supports drag and drop, CORS, and multiple file uploading with progress bars. Works in IE7-9, mobile, and all modern browsers.

var uploader = new ss.SimpleUpload({
      button: 'upload-btn', // HTML element used as upload button
      url: '/PathTo/UploadHandler', // URL of server-side upload handler
      name: 'uploadfile' // Parameter name of the uploaded file
});

Features

• Cross-browser -- works in IE7+, Firefox, Chrome, Safari, Opera
• Supports multiple, concurrent file uploads (even in non-HTML5 browsers)
• Built-in CORS support
• Drag and drop file uploads (new in v2.0)
• No flash or external CSS -- a single 6Kb Javascript file (minified and gzipped)
• Progress bars in all browsers, including IE9 and older. Built-in support for:
  • Nginx Upload Progress Module
  • PHP APC File Upload Progress
  • PHP Session Upload Progress
• Use any HTML element as the upload button
• No dependencies - use it with or without jQuery
• Provides individual callback functions for XHR-supported browsers and for browsers that do not support XHR uploads
• Ability to pass custom headers in request such as the Authorization header

Frequently Asked Questions

Visit the new FAQ for solutions to the most common issues.

How to Use

Live Demo
API Reference
Upload progress bars in IE9 (and older)
CORS — Cross-domain file uploading with Simple Ajax Uploader

There are two main ways to use the plugin:

1. Single file uploading - Only one upload allowed at a time. Progress bar is an element that is re-used for each upload.
2. Multiple file uploading - Allow multiple, concurrent file uploads. Progress bars are created on the fly before each upload.

Method 1: Single file uploading (one file at a time)

Before each upload, in the onSubmit() callback function, the on-page sizeBox and progress elements are assigned specific roles using these two functions:

setProgressBar(elem) - Designates an element as the progress bar for an upload.
setFileSizeBox(elem) - Designates an element as the container in which the file size of an uploading file will be inserted.

As a result, when an upload begins, the file size of the upload is inserted into the sizeBox element and the CSS width of the progress element is set to 0%. As the upload progresses, the CSS width percentage of the progress element will be updated accordingly.

This approach of assigning roles to elements provides developers with a great deal of flexibility -- progress indicators can be styled in any way and placed anywhere on the page.

var sizeBox = document.getElementById('sizeBox'), // container for file size info
    progress = document.getElementById('progress'); // the element we're using for a progress bar
 
var uploader = new ss.SimpleUpload({
      button: 'uploadButton', // file upload button
      url: 'uploadHandler.php', // server side handler
      name: 'uploadfile', // upload parameter name        
      progressUrl: 'uploadProgress.php', // enables cross-browser progress support (more info below)
      responseType: 'json',
      allowedExtensions: ['jpg', 'jpeg', 'png', 'gif'],
      maxSize: 1024, // kilobytes
      hoverClass: 'ui-state-hover',
      focusClass: 'ui-state-focus',
      disabledClass: 'ui-state-disabled',
      onSubmit: function(filename, extension) {
          this.setFileSizeBox(sizeBox); // designate this element as file size container
          this.setProgressBar(progress); // designate as progress bar
        },         
      onComplete: function(filename, response) {
          if (!response) {
              alert(filename + 'upload failed');
              return false;            
          }
          // do something with response...
        }
});        

Method 2: Multiple file uploads

Below is an example of how to implement multiple file uploading with progress bars. A new progress bar is created for each file upload within the onSubmit() callback function.

Like in Method 1, the newly created elements are assigned roles using the setProgressBar() and setFileSizeBox() functions. Unlike the previous example, however, the progress elements are automatically removed when the upload is completed.

var uploader = new ss.SimpleUpload({
      button: 'uploadButton',
      url: 'uploadHandler.php', // server side handler
      progressUrl: 'uploadProgress.php', // enables cross-browser progress support (more info below)
      responseType: 'json',
      name: 'uploadfile',
      multiple: true,
      allowedExtensions: ['jpg', 'jpeg', 'png', 'gif'], // for example, if we were uploading pics
      hoverClass: 'ui-state-hover',
      focusClass: 'ui-state-focus',
      disabledClass: 'ui-state-disabled',   
      onSubmit: function(filename, extension) {
          // Create the elements of our progress bar
          var progress = document.createElement('div'), // container for progress bar
              bar = document.createElement('div'), // actual progress bar
              fileSize = document.createElement('div'), // container for upload file size
              wrapper = document.createElement('div'), // container for this progress bar
              //declare somewhere: <div id="progressBox"></div> where you want to show the progress-bar(s)
              progressBox = document.getElementById('progressBox'); //on page container for progress bars
          
          // Assign each element its corresponding class
          progress.className = 'progress progress-striped';
          bar.className = 'progress-bar progress-bar-success';
          fileSize.className = 'size';
          wrapper.className = 'wrapper';
          
          // Assemble the progress bar and add it to the page
          progress.appendChild(bar); 
          wrapper.innerHTML = '<div class="name">'+filename+'</div>'; // filename is passed to onSubmit()
          wrapper.appendChild(fileSize);
          wrapper.appendChild(progress);                                       
          progressBox.appendChild(wrapper); // just an element on the page to hold the progress bars    
          
          // Assign roles to the elements of the progress bar
          this.setProgressBar(bar); // will serve as the actual progress bar
          this.setFileSizeBox(fileSize); // display file size beside progress bar
          this.setProgressContainer(wrapper); // designate the containing div to be removed after upload
        },
        
       // Do something after finishing the upload
       // Note that the progress bar will be automatically removed upon completion because everything 
       // is encased in the "wrapper", which was designated to be removed with setProgressContainer() 
      onComplete:   function(filename, response) {
          if (!response) {
            alert(filename + 'upload failed');
            return false;
          }
          // Stuff to do after finishing an upload...
        }
});

For multiple file uploads, we use an additional function: setProgressContainer(elem). This function designates an element to be removed from the DOM after the upload is completed.

In the example, the element set to be removed with setProgressContainer() is the outer container for the progress elements. As a result, progress bars will be removed from the DOM after each upload is completed.

Form Integration

To integrate the plugin with an existing form so that file uploads include all input fields contained in the form, simply pass the form element to the form option, or use the setForm( form ) instance method.

Form integration respects any HTML5 validation attributes. Invalid input values will prevent the upload from occurring.

By default, the plugin will override native submission of the form. Submit attempts will be caught and instead files will be uploaded along with the form data. To disable this behavior, set the overrideSubmit to false. Setting overrideSubmit to false will require that the submit instance method be manually called in order to upload files and form data together.

Note: Only use form integration if a file upload is required to be submitted with the form.

Cross-Browser Helper Functions

To ease the pain of supporting older browsers, the plugin includes a set of callback functions which allow specific behavior to be defined based on whether the user's browser supports XHR uploads/HTML5 File API:

startXHR(filename, fileSize) - Called prior to upload -- only in browsers that support XHR uploads
endXHR(filename) - Called after upload is completed -- only in browsers that support XHR uploads
startNonXHR(filename) - Called prior to upload -- only in browsers that do not support XHR uploads
endNonXHR(filename) - Called after upload is completed -- only in browsers that do not support XHR uploads

A common use case is to show an upload progress bar in browsers that support the progress event while displaying an animated GIF in older browsers:

 
var progress = document.getElementById('progress'), // progress bar
    loaderImg = document.getElementById('loaderImg');  // "loading" animated GIF
                
var uploader = new ss.SimpleUpload({
      button: 'uploadButton',
      url: 'uploadHandler.php', // server side handler
      responseType: 'json',
      name: 'uploadfile',
      hoverClass: 'ui-state-hover',
      focusClass: 'ui-state-focus',
      disabledClass: 'ui-state-disabled',
      startXHR: function(filename, size) {                   
          progress.style.display = 'inline-block'; // show progress bar            
          this.setProgressBar(progress); // designate as progress bar
      },
      endXHR: function(filename) {
          progress.style.display = 'none'; // hide progress bar
      },
      startNonXHR: function(filename) {
          loaderImg.style.display = 'inline-block'; // show animated GIF
      },
      endNonXHR: function(filename) {
          loaderImg.style.display = 'none'; // hide animated GIF
      }
});

Returning false from startXHR() and startNonXHR() will prevent the upload from starting, just as it does with onSubmit() and onChange().

Server-side file handling

Files are uploaded by POST as either raw form data or regular multipart/form-data, depending on the browser.

Using Uploader.php

Note: This PHP class is included only for convenience. It is not required to use PHP with Simple Ajax Uploader. The plugin is agnostic to server configuration, so use any language you prefer.

<?php
require('Uploader.php');
 
$upload_dir = '/img_uploads/';
$valid_extensions = array('gif', 'png', 'jpeg', 'jpg');
 
$Upload = new FileUpload('uploadfile');
$result = $Upload->handleUpload($upload_dir, $valid_extensions);
 
if (!$result) {
    echo json_encode(array('success' => false, 'msg' => $Upload->getErrorMsg()));   
} else {
    echo json_encode(array('success' => true, 'file' => $Upload->getFileName()));
}

You can also save the uploaded file with a different name by setting the newFileName property:

$Upload = new FileUpload('uploadfile');
$ext = $Upload->getExtension(); // Get the extension of the uploaded file
$Upload->newFileName = 'customFileName.'.$ext;
$result = $Upload->handleUpload($upload_dir, $valid_extensions);

To access the newly uploaded file, use the getSavedFile() method to get the file's path after the upload is completed:

$Upload = new FileUpload('uploadfile');
$result = $Upload->handleUpload($upload_dir, $valid_extensions);
 
if ($result) {
  $path = $Upload->getSavedFile();
  $imgsize = getimagesize($path);
  // image resizing stuff...
}

Passing Custom Headers

var uploader = new ss.SimpleUpload({
    customHeaders: {'Authorization': 'my-access-token'},
    ...
});
 

Drag and Drop

Enable drag and drop uploading by passing an element to the dropzone option to serve as the drop zone:

var uploader = new ss.SimpleUpload({
      dropzone: 'dragbox', // ID of element to be the drop zone
      url: 'uploadHandler.php',
      name: 'uploadfile',
      responseType: 'json',      
      onComplete: function(filename, response) {
          // do something with response...
      }
}); 

License

Released under the MIT license.