Question

getGood = function(v,x) {
    $.getJSON('json/products.json', function(data) {
        $.each(data, function(key, val) {
            if (v.toLowerCase() == key.toLowerCase()) {
                $.each(val.products, function(ckey, cval) {
                    if (x.toLowerCase() == ckey.toLowerCase()) {
                        var dval=new Date().getDay();
                        var qHash=hex_md5(v+x+qs('cst')+dval).toLowerCase();    
                        if (qHash == qs('hash')) {
                            return dval;
                        } else {
                            window.location.replace('/errors/418.html');
                        }
                    }                
                });
            }
        });
    });
}

$(document).ready(function() {
    var owner=getGood(qs('cat'),qs('subp'));
    alert(owner==null);
    $('.content_title').html(qs('subp'));
    $('.description').html(owner.descripion);
})

The above code is supposed to read a JSON file, compare some query strings to test for validity and then return the object if the request is valid. Problem is, no matter what I do, getGood refuses to return any value to my owner variable. I’ve tried having it return the different values around it. I was just trying to get it to return anything I could. It needs to return cval. The alert at the bottom, however, always says “undefined/null”.

EDIT

Because apparently people think I am just that retarded:

YES, it gets to the return statement. Yes, qHash == qs(‘hash’), I’m not asking you to check every if/loop/etc. I already know all of that works. I’m asking, why does my return statement not end up setting owner to what it is supposed to.

Answer 1

The callback passed to “$.getJSON()” is executed asynchronously. It is therefore just not possible to return a value from it.

Instead, pass in the code that needs to act on the value as a function parameter. The callback function can then pass the value into that function as a parameter.

function getGood(v, x, handleOwner) {
  $.getJSON('json/products.json', function(data) {
      $.each(data, function(key, val) {
          if (v.toLowerCase() == key.toLowerCase()) {
             $.each(val.products, function(ckey, cval) {
                if (x.toLowerCase() == ckey.toLowerCase()) {
                    var dval=new Date().getDay();
                    var qHash=hex_md5(v+x+qs('cst')+dval).toLowerCase();    
                    if (qHash == qs('hash')) {
                        handleOwner(dval); // calling the handler function here
                    } else {
                        window.location.replace('/errors/418.html');
                    }
                }                
            });
        }
     });
  });
}

//
getGood(qs('cat'),qs('subp'), function(owner) {
  alert(owner);
});