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I would like to know if it is possible to do something like this:

if (mb == null || typeof (mb) != "object") {
    var mb = new Object();
}


mb = {
    tests: {
        onAnimals: {
            test: function() {
                return "";
            }
        }
        onHumans: {
            test: function() {
                return "";
            }
        }
    }
}

Bu when I tries it, I can see Tests, but when I dot further in, I can't se onAnimals / onHumans.

javascript is still new to me, so hope you can help.

I would like to know if it is possible to do something like this:

if (mb == null || typeof (mb) != "object") {
    var mb = new Object();
}


mb = {
    tests: {
        onAnimals: {
            test: function() {
                return "";
            }
        }
        onHumans: {
            test: function() {
                return "";
            }
        }
    }
}

Bu when I tries it, I can see Tests, but when I dot further in, I can't se onAnimals / onHumans.

javascript is still new to me, so hope you can help.

• javascript
• class-design

Share Improve this question Follow edited Dec 21, 2009 at 7:35 Cheeso 193k106106 gold badges485485 silver badges734734 bronze badges asked Dec 3, 2009 at 15:35 JoshloJoshlo 79444 gold badges99 silver badges2626 bronze badges

Add a ment  | 

5 Answers 5

Sorted by: Reset to default 7

You're missing a ma before onHumans. I've assumed mb to be a global variable; you can use var instead if that's what you need. Also, it's easier to read if you structure it differently, like this:

window.mb = window.mb || {};
window.mb = {
  tests: {
    onAnimals: {
      test: function(){
        return "";
      }
    },
    onHumans: {
      test: function(){
        return "";
      }
    }
  }
};

You are missing a ma before onHumans

if (mb == null || typeof (mb) != "object") {
    var mb = new Object();
}

mb = {
    tests: {
        onAnimals: {
            test: function() {
                return "animal";
            }
        },
        onHumans: {
            test: function() {
                return "human";
            }
        }
    }
}

alert(mb); //[object Object]
alert(mb.tests); //[object Object]
alert(mb.tests.onAnimals); //[object Object]
alert(mb.tests.onHumans); //[object Object]
alert(mb.tests.onAnimals.test()); //animal
alert(mb.tests.onHumans.test()); //human

You don't need to declare the variable as an object beforehand, simply using the brackets like that is all you need. You do have a syntax error, missing a mas before "onHumans", but aside from that, it looks good to me. You should be able to reach the functions via mb.tests.onAnimals.test and mb.tests.onHumans.test

Your code is mostly valid, and you don't even have to do the initial if-check. Just type var mb = { ..., and you'll start set mb to a new object, regardless of whether it was one before, or undefined, or something else...

What you're missing is a ma after the onAnimals declaration tho:

mb = {
    tests: {
        onAnimals: {
            test: function() {
                return "";
            }
        },
        onHumans: {
            test: function() {
                return "";
            }
        }
    }
}

As stated in some of the ments above testing for the existence of the variable mb is redundant when you just re-declare it to append your methods and properties.

If you are testing for the existence of the variable to add additional methods to the object you should use a method like jQuery's extend or ExtJs's apply method.

jQuery:

window.mb = $.extend(window.mb||{}, {
    tests: {
        onAnimals: {
            test: function() {
                return "";
            }
        },
        onHumans: {
            test: function() {
                return "";
        }
    }
});

Ext:

window.mb = Ext.apply(window.mb||{}, {
    tests: {
        onAnimals: {
            test: function() {
                return "";
            }
        },
        onHumans: {
            test: function() {
                return "";
        }
    }
});

This snippet of code will either append the tests object to the existing mb variable or create the mb variable then append the tests object to it.

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