Check if a object is defined, best practice.

Question

I have the following JSON response from a ajax-request.

var json = {
    \"response\": {
        \"freeOfChargeProduct\": {  
        \"description\": \"Prod         


        

Answer 1

You could do something like this:

try{
    var focp = json.response.freeOfChargeProduct
    var text = "You get " + focp.qty + " of " +
        focp.productName +
        " for only $" + (focp.qty-focp.details.focQuantity)*focp.details.price +
        ", You save $" + focp.details.focQuantity*focp.details.price;
    $("order_info").innerText = text;
} catch(e) {
    // woops, handle error...
}

It would generate a message like this from the provided data in your question if the fields exists:

You get 6 of XYZ for only $277,5, You save $55.5

If the data is non-existing, you'll end up in the catch block. You could always just to a Try, Catch, Forget here if you can't come up with a way to handle the error (Maybe do a new AJAX request for the data?).