RsD0p9BK
11/28/2016 - 4:07 AM

typeof.js

// Detecting an undefined object property

if (typeof something === "undefined") {
  alert("something is undefined");
}

if (typeof my_obj.someproperties === "undefined"){
  console.log('the property is not available...'); // print into console
}

// http://stackoverflow.com/questions/27509/detecting-an-undefined-object-property