问如何在发送表单信息后使用javascript/jquery重置表单

EN

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script>
function fetch() {

        setTimeout( function() {
        loadDoc();
        fetch();
    }, 100);

}


function loadDoc() {
  var xhttp = new XMLHttpRequest();
  xhttp.onreadystatechange = function() {
    if (this.readyState == 4 && this.status == 200) {
      myFunction(this);
    }
  };
  xhttp.open("GET", "../clubs/club.xml", true);
  xhttp.send();
}

$(function() {
    $("#formpost").submit(function(event) {
        event.preventDefault();

        var form = $(this);
        var url = form.attr('action');

        $.ajax({
            type: "POST",
            url: url,
            data: form.serialize() // serializes the form's elements.
        }).done(function(data) {
            var msg = $(data).find('#msg').text();


        });
    });
});  

  function myFunction(xml) {
  var rowsArray =[]
  var i , j;
  var xmlDoc = xml.responseXML;
  var table="";
  var x = xmlDoc.getElementsByTagName("messageset");
  for (i = 0; i < x.length; i++) {
  var name = x[i].getElementsByTagName("name")[0].childNodes[0].nodeValue;
  var time = x[i].getElementsByTagName("time")[0].childNodes[0].nodeValue;
    var row = "<div class=\"row\"><div class=\"b1\" ><img src=\"" + "../users/"    
    + name +"/notification/profilepic.svg" + "\" width=\"30px\" height=\"30x\" alt=\"avatar\" style=\"border-radius: 45px;\" class=\"image\" ></div><div class=\"b2 msginname\" >" +
    x[i].getElementsByTagName("name")[0].childNodes[0].nodeValue +
    "</div> <div class=\"cmoti \"><a href=\"online.php\">check motive</a></div><div class=\"msgoriginal\">" +
    x[i].getElementsByTagName("message")[0].childNodes[0].nodeValue + "</div></div>";
    rowsArray.push(row)
  }
  table += rowsArray.reverse().join('');
  document.getElementById("demo").innerHTML = table;
  document.getElementById("check").innerHTML = time ;
}
function myFun(){
 $('#formpost').click(function(){
        $('#formpost')[0].reset();
  });
}
</script>