Calling a user defined jQuery function

Question

I'm a javascript newbie and I'm trying to call a jQuery function in this way:

function getProducts(){
      $.post("products.php",
      {
        customer_ID:$("#customers").val()
      },
      function(data,status){
        return status && data !== "";
      });
};

$(document).ready(function(){
    $("#customers").change(function(){
        if(getProducts){
            alert("trovato");

            $("#products").prop("disabled", false);
            $("#products").html(data);
        }else{
            alert("non trovato");

            $("#products").empty();
            $("#products").prop("disabled", true);
        }
    });
});

The if-else statement in the ready doesn't work although the function getProducts works properly. The problem, I suppose, is in the function call. What am I wrong with this? Thank you.

See here, answered many times http://stackoverflow.com/questions/14220321/how-to-return-the-response-from-an-ajax-call — elclanrs, Feb 04 '14 at 08:51
Yeah, elclanrs pointed that out. Figured I should point out the obvious syntax error. — Hless, Feb 04 '14 at 08:54
One other little question: does a javascript function has to terminate with a ; after the } bracket? — superpuccio, Feb 04 '14 at 09:21

score 0 · Accepted Answer · answered Feb 04 '14 at 08:57

0

You need to wrap the response with a callback, like so:

function getProducts(callback){
      $.post("products.php",
      {
        customer_ID:$("#customers").val()
      },
      function(data,status){
         callback(status && data !== "");
      });
};

$(document).ready(function(){
    $("#customers").change(function(){
        getProducts(function(status) {
           if(status){
             alert("trovato");

             $("#products").prop("disabled", false);
             $("#products").html(data);
           }else{
             alert("non trovato");

             $("#products").empty();
             $("#products").prop("disabled", true);
           }
        });

    });
});

answered Feb 04 '14 at 08:57

Hless

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1

I think that the syntax of these javascript things is a bit messy, but yes, this is the solution :) – superpuccio Feb 04 '14 at 09:03
What is messy about it exactly? I forgot a few spaces but smashed this together in a few seconds. The way the callback gets passed around isn't messy though, it's how javascript works.. – Hless Feb 04 '14 at 09:05
Nono, it's clear and it's ok! I didn't "argue" with you or with your solution, but with the javascript syntax (the javascript Modus Operandi) – superpuccio Feb 04 '14 at 09:08
Yeah I guess it's a bit weird if you're a javascript beginner (or new to functional programming for that matter). But you'll get used to it after a while. – Hless Feb 04 '14 at 09:10

score -1 · Answer 2 · answered Feb 04 '14 at 08:54

I'm not quite sure if this will work because of the asynchronized call inside of the function.

The obvious mistake is that you have to call a function like that: function(). You just forgot the parentheses.

If it won't work after that fix, you have to rework your program to use callbacks where you have asynchron calls.

Calling a user defined jQuery function

2 Answers2