当我通过ajax将base64代码传递给php时，它不会发送完整的代码。 我该如何解决呢

Question

When i pass base64 code to php through ajax it doesn't send full code. It receives only half codes from top remaining codes are missing. How to send full code using ajax jquery. Can you please help me to solve this problem. Here my code,

Here my php code,

if(isset($_POST['img_url'])){

    $img = $_POST['img_url'];
    echo $img;
}

Here my js code,

var img_url = "my base64 code for image";

      $.ajax({
        type: "post",
        url: "http://www.aaaaa.com/jobsadmin/ajax_page.php",
        data: "img_url="+img_url,
        success:function(html){
          alert(html);
        }
      })