https://online-marketing-forum.com/wp-content/plugins/toolbox-for-…//assets/image-upload.js?ver=7.1.2

1function tfaf_file_upload(field_id) {
2
3    const uploadForm = '<form id="tfaf_file_form" action="?tfaf_do_upload=1" method="post" target="tfaf_file_frame"' +
4        'enctype="multipart/form-data" onsubmit="tfaf_file_upload_submit();" data-field-id="' + field_id + '">' +
5        '<input type="file" name="tfaf_file" id="tfaf_file" tabindex="-1" onchange="jQuery(this).parent().submit();" />' +
6        '<iframe id="tfaf_response_frame" name="tfaf_file_frame" />';
7
8    jQuery('#tfaf_file_form, #tfaf_response_frame').remove();
9    jQuery('#' + field_id).parent().css('overflow', 'hidden')
10        .append(uploadForm);
11
12    jQuery('#tfaf_file').trigger('click');
13
14}
15
16function tfaf_file_upload_submit() {
17    const responseFrame = jQuery('#tfaf_response_frame');
18
19    responseFrame.load(function () {
20        let response = responseFrame.contents().find('body').text();
21        if (!(response.startsWith('https://') || response.startsWith('http://'))) {
22            if (response.startsWith('size-error')){
23                // Get max upload size
24                let max_size = response.split(']');
25                max_size = max_size[0].split('[')[1];
26                alert('Error: The image must be smaller then ' + max_size + ' MB.');
27            } else if (response.startsWith('[[tfaf_debugging_mode]]')) {
28                alert(response);
29            } else {
30                alert('Error: The image upload was not successful. Please check your image and try it again. Only PNG, GIF or JPEG files are allowed.');
31            }
32            response = '';
33        }
34        jQuery('#' + jQuery('#tfaf_file_form').data('field-id')).val(response).prop('disabled', false);
35        responseFrame.off('load');
36    });
37    jQuery('#' + jQuery('#tfaf_file_form').data('field-id')).prop('disabled', true).val('Please wait...');
38
39    return true;
40}