Question

$.each(json.data,function(i,fb){

//some code here...

if (msg.length > 150) {
                msg = msg.substr(0,200)+"...";
            }

//more code here...
});

I have an issue here. If msg is not defined I got an error and I got nothing displayed on the browser.

Possible Solution: create a default message for the cases where msg is not defined.

Try:

if (msg = 'undefined') {
 msg = 'some default message';
} else if (msg.length > 150) {
msg = msg.substr(0,200)+"...";
}

Issue:
The above try didn’t work because I get for each item, the same default message, instead of having the default message only for those cases were msg is no “set”.

Request:
Can I have your help in order to write the proper code so that, on each item, if msg is not defined show a default one, if otherwise, it’s site, display it ?

If you lack some information in order to proper help me, please, let me know. I’m really on a bad position right now. :s

Thanks a lot,
MEM

Answer 1

You have to write == rather than = in your if-statement. Also, if you’re trying to test if it’s undefined, you should use typeof, like this:

if (typeof msg == 'undefined')

This idea of comparing it using typeof is actually safer than comparing it to the object called undefined. The reason is that the object can be redefined, but the result of typeofnever changes. I dont know why anyone would be crazy enough to do it, but it is possible to write:

undefined = "hi there";
if (msg == undefined) // oh noes!
  ...
if (typeof msg == "undefined") // still works!