CODE EXAMPLE FOR PHP

upload multiple image using jquery ajax in codeigniter

<script type="text/javascript" src="https://code.jquery.com/jquery-3.4.1.min.js"></script>
        <script type="text/javascript">
            $(document).ready(function (e) {
                $('#upload').on('click', function () {
                    var form_data = new FormData();
                    var ins = document.getElementById('multiFiles').files.length;
                    for (var x = 0; x < ins; x++) {
                        form_data.append("files[]", document.getElementById('multiFiles').files[x]);
                    }
                    $.ajax({
                        url: 'ajaxmultiplefileupload/upload_files', // point to server-side controller method
                        dataType: 'text', // what to expect back from the server
                        cache: false,
                        contentType: false,
                        processData: false,
                        data: form_data,
                        type: 'post',
                        success: function (response) {
                            $('#msg').html(response); // display success response from the server
                        },
                        error: function (response) {
                            $('#msg').html(response); // display error response from the server
                        }
                    });
                });
            });
</script>