[imedia]

<form action="" id="post_form" method="post" onsubmit="query_send()">
</form>

function query_send(e){
var elem = document.getElementById('end');
var start = document.getElementById('start');
e.preventDefault();
post_ajax_(start,end);
  
     
function post_ajax_(start,end){
$.ajax({
            url: '/server/make_letter.php',  
            type: "POST",         
            data:   ({start:start,end:end}),       
            cache: false,
            error: function (xhr, ajaxOptions, thrownError) {
               /*  alert(" write json item, Ajax error! " + xhr.status + " error =" + thrownError + " xhr.responseText = " + xhr.responseText );    */ 
            },
            success: function (data) {
               console.log(data);
            } 
    });
}

}