phpmyadmin/js/transformations/image_upload.js

/* vim: set expandtab sw=4 ts=4 sts=4: */
/**
 * Image upload transformations plugin js
 *
 * @package PhpMyAdmin
 */

AJAX.registerOnload('transformations/image_upload.js', function() {
    // Change thumbnail when image file is selected
    // through file upload dialog
    $('input.image-upload').on('change', function(event) {
        if (this.files && this.files[0]) {
            var reader = new FileReader();
            var $input = $(this);
            reader.onload = function (e) {
                $input.prevAll('img').attr('src', e.target.result);
            };
            reader.readAsDataURL(this.files[0]);
        }
    });
});

/**
 * Unbind all event handlers before tearing down a page
 */
AJAX.registerTeardown('transformations/image_upload.js', function() {
    $('input.image-upload').off('change');
});