How to run getJSON sequentially

Question

I'm trying to embed a weather forecast for a specific date on my webpage. Here's excepts from my code on a test page http://elhuracantango.com/pogoda that I can't get to work properly:

<script>
function b(date){
$.getJSON(url + apiKey + "/" + lati + "," + longi + ","+ date+ "?units=si&lang=ru&exclude=hourly&callback=?", 
function(data) {
 $('#weather').append(weekdays[dateobj.getDay()] + " : "+ data.daily.data[0].summary))
}
b("2015-06-25T12:00:00");
b("2015-06-26T12:00:00");
b("2015-06-27T12:00:00");
b("2015-06-28T12:00:00");
</script>

But the forecast on the webpage doesn't always get displayed sequentially.

Answer 1

Its a async operation so you can't guarantee which one will return result first. You have to use callback / promise to deal with this.

If are trying to update the weather at specific interval of time. Use setInterval

eg:

function b(date){ 
  var result = // ajax call here.

  return result 
}


setInterval(function(){
     var html = b(new Date());
     $('#result').html(html);
}, 1000);