title: Simple JavaScript empty string check, what does (an empty string) mean and why is it failing?
body: <p>Here's my code:</p>
  
  <pre><code>$("#ddlCiudad").change(function () {
      var idCity = $("#ddlCiudad").val();
      $.getJSON("/ProductCheckout/GetPriceForLocation", { cityId: idCity, productId: idProduct, type: "land" },
          function (cityData) {
  
              console.log("Recieved json data.");                    
  
              landCost = cityData.LandCost;
              $("#billingshippingcost").text(landCost);
              console.log("Assigned value of LandCost");
  
              airCost = cityData.AirCost;
              console.log("Assigned value of AirCost");
  
              console.log(landCost); //Logs: 25,00
              console.log(airCost); //Logs: "(an empty string)"
  
              if (landCost == "") {
                  $(".land").removeClass("land").addClass("land-disabled");
              }
              else {
                  $(".land-disabled").removeClass("land-disabled").addClass("land");
              }
  
              if (airCost = "") {
                  $(".air").removeClass("air").addClass("air-disabled");
              }
              else {
                  $(".air-disabled").removeClass("air-disabled").addClass("air");
              }
  
          }
      );
  });
  </code></pre>
  
  <p>That <code>if</code> statement is <strong>not</strong> being fired, any suggestions on why it's not firing?</p>
  
  <p>Maybe <code>an empty string</code> isn't the same as "" in Javascript.</p>