为什么PDO不将+和&的符号保存到数据库中？

Question

为什么我在文本区键入"+-1-23$%^&sdfsdf/><"，但它只将"-1-23$%^"保存到数据库中？

代码：

function postingMsg (){
        $('.error').hide();
    var messageposting2= $("textarea#messageposting").val();
        var dataString = 'messageposting2='+ messageposting2;
        $.ajax({
             type: "POST",
             url: "note-send.php",
             data: dataString,
             success: function(msg) {
         msg = parseFloat(msg)      
             }
        });
        return false;   
}
if ((isset($_POST['messageposting2'])) && (strlen($_POST['messageposting2']) > 0)) {
    $messageposting3 = $_POST['messageposting2'];   
    $sql = "UPDATE users 
            SET my_note=?
            WHERE user_id=?";
    $q = $conn->prepare($sql);
    $q->execute(array($messageposting3, $_SESSION['user_id']));
    echo "1";
} else {echo "0";}

Answer 1

它与PDO或数据库无关。在通过Ajax发送字符串之前，必须对其进行URL编码。

var dataString = 'messageposting2='+ encodeURIComponent(messageposting2);