Append variables to Jquey.post

Append variables to Jquey.post

I'm using post for sending data to a PHP page. My problem is that sometimes I need to append some more variables to the POST statement and I wanna use the same function.

The basic is:
$.post( 'mypage.php', {
    var1: 'data',
    var2: 'data'
  },
  function() {
    $('#obj').html(data);
  });


But sometimes I need:

$.post( 'mypage.php', {
    var1: 'data',
    var2: 'data',
    var3: 'data',
    var4: 'data'
  },
  function() {
    $('#obj').html(data);
  })


Is there a way to use the same function for doing this?