Ajax无法与wpdb一起使用

Question

I have Simple code i had Created in Ajax,PHP and Mysql this code work fine in all Conditions Except one this one is wpdb Code to insert Data to table

    <script type="text/javascript">
function _(id){ return document.getElementById(id); }
function submitForm(){
    _("status").innerHTML = 'please wait ...';
    var formdata = new FormData();
    formdata.append( "m", _("m").value );
    var ajax = new XMLHttpRequest();
    ajax.open( "POST", "<?php bloginfo('template_directory'); ?>/ajax-insert.php" );
    ajax.onreadystatechange = function() {
        if(ajax.readyState == 4 && ajax.status == 200) {
            if(ajax.responseText == "empty"){
                _("status").innerHTML = '<div class="error"><p>Please Fill all of the Fields</p></div>';
            }
            if(ajax.responseText == "Done"){
                _("status").innerHTML = '<div class="success"><p>Done</p></div>';
            }
            if(ajax.responseText == "error"){
                _("status").innerHTML = '<div class="success"><p>Problem</p></div>';
            }
        }
    }
    ajax.send( formdata );
}
</script>
<form action="" onsubmit="submitForm(); return false;">
        <div id="status"></div>
    <label>Your Message</label><br>
    <textarea cols="50" rows="10" type="text" name="m" id="m"></textarea>
        <br>
    <input name="submit" type="submit" value="Send">
</form>

ajax-insert.php i had make code to insert data with some Conditions this is the code

<?php 
    if(isset($_POST['m'])){
        $message = $_POST['m'];
        date_default_timezone_set("Africa/Cairo");
        $date = date("Y/m/d h:i:sa");
    }if(empty($message))
        echo "empty";
    elseif(!preg_match("~^[0-9a-z\-'\s\p{Arabic}]{1,60}$~iu", $message)){
        echo "error";
    }else{
        echo "Done";
        $insert = $wpdb->insert( 'chat_support', array( 'id' => '1', 'message' => $message , 'date' => $date, 'user' => $user_ID));
    }
?>

if i try submit the form while textarea is Empty it give me Response that it is Empty but the Problem When i Write any thing to submit in database the code after Else dosen't work The response be Please wait..... and This Response Still more thime without Doing and Thing

Answer 1

It is Highly advisable to use WordPress Ajax actions, you need to hookup your function to be called to wp_ajax and it would be available throughout the wp environment

Details about how to create and call ajax functions can be viewed from here https://codex.wordpress.org/AJAX_in_Plugins