Using jQuery $.ajax to post json encoded data to a php script: success event is doing nothing -

i making ajax call using jquery post data json php file, nothing happening on success. code below :

ajax section

$.ajax({     url:"mydata.php",     datatype: 'json',     method:"post",     data:'country',                           success:function(j){         var $country = $("#country");         $.each(j, function () {                $country.append($('<option></option>').attr("value", this.country_id).text(this.country_name));         });     } });   

php section

if(isset($_request['country'])){     $conn=new mysqli("localhost","root","","newdb");     $myquery="select * country";      $result=$conn->query($myquery);      while($country=$result->fetch_assoc()){         echo json_encode($country);     } } 

html section

<label >country:</label> <select class="form-control"  id="country" >     <option>---select---</option> </select> 

you need collect countries in array echo json.

$countries = []; if(isset($_request['country'])){     $conn=new mysqli("localhost","root","","newdb");     $myquery="select * country";      $result=$conn->query($myquery);      while($country=$result->fetch_assoc()){         $countries[] = $country;     }      echo json_encode($countries); } 

also in js send country parameter.

... method:"post", data: {country : true}, ...