jquery $.post

var formData = {name:"John", surname:"Doe", age:"31"}; //Array 

$.ajax({
    url : "https://example.com/rest/getData", // Url of backend (can be python, php, etc..)
    type: "POST", // data type (can be get, post, put, delete)
    data : formData, // data in json format
  	async : false, // enable or disable async (optional, but suggested as false if you need to populate data afterwards)
    success: function(response, textStatus, jqXHR) {
    	console.log(response);
    },
    error: function (jqXHR, textStatus, errorThrown) {
		console.log(jqXHR);
      	console.log(textStatus);
      	console.log(errorThrown);
    }
});

<script type="text/javascript">
    function send() {
        var person = {
            name: $("#id-name").val(),
            address:$("#id-address").val(),
            phone:$("#id-phone").val()
        }

        $('#target').html('sending..');

        $.ajax({
            url: '/test/PersonSubmit',
            type: 'post',
            dataType: 'json',
            contentType: 'application/json',
            success: function (data) {
                $('#target').html(data.msg);
            },
            data: JSON.stringify(person)
        });
    }
</script>

$.ajax({
  type: "POST",
  url: url,
  data: data,
  success: success,
  dataType: dataType
});

$(function(){
    $('#myForm').on('submit', function(e){
      e.preventDefault();
      $.post('http://www.somewhere.com/path/to/post', 
         $('#myForm').serialize(), 
         function(data, status, xhr){
           // do something here with response;
         });
    });
});

// Assign handlers immediately after making the request,
// and remember the jqxhr object for this request
var jqxhr = $.post( "example.php", function() {
  alert( "success" );
})
  .done(function() {
    alert( "second success" );
  })
  .fail(function() {
    alert( "error" );
  })
  .always(function() {
    alert( "finished" );
  });
 
// Perform other work here ...
 
// Set another completion function for the request above
jqxhr.always(function() {
  alert( "second finished" );
});

$("button").click(function(){

  $.post("demo_test.asp", function(data, status){

    alert("Data: " + data + "\nStatus: " + status);

  });

});
 

const postData = async ( url = '', data = {})=>{
    console.log(data);
      const response = await fetch(url, {
      method: 'POST', 
      credentials: 'same-origin',
      headers: {
          'Content-Type': 'application/json',
      },
     // Body data type must match "Content-Type" header        
      body: JSON.stringify(data), 
    });

      try {
        const newData = await response.json();
        console.log(newData);
        return newData;
      }catch(error) {
      console.log("error", error);
      }
  }