How to check if JSON return is empty with jquery

Just test if the array is empty.

$.getJSON(url,function(json){
    if ( json.length == 0 ) {
        console.log("NO DATA!")
    }
});

Below code(jQuery.isEmptyObject(anyObject) function is already provided) works perfectly fine, no need to write one of your own.

   // works for any Object Including JSON(key value pair) or Array.
  //  var arr = [];
  //  var jsonObj = {};
    if (jQuery.isEmptyObject(anyObjectIncludingJSON))
    {
       console.log("Empty Object");
    }

if (!json[0]) alert("JSON empty");