My previous post contained a small piece of code explaining how to loop through object properties with the Reflection namespace in C#.

In this post, I'd like to explain how to loop through a JavaScript object.

Let's create an object in JavaScript:

var myObject = {
    Name: "Elad",
    LastName: "Shalom",
    Age: 26,
    Kids: ["Daniel"]
};

This object contains four properties:

1. Name (string)
2. LastName (string)
3. Age (int)
4. Kids (array)

Now for the loop part:

function LoopThroughProperties(obj)
{
    for (var propName in obj) 
    {
        alert(propName + ": " + obj[propName]); 
    }
}

The function will receive an object and loop through all of its properties.

I'd like to explain a bit about the for syntax I used. Those of you who write in C#/ VB/ Java will find it very similar to the foreach loop in JavaScript.

Since an object in JavaScript is a form of array, I can easily call every one of its properties the same way (almost) I'd call them when looping through an array. This type of foreach loop in JavaScript is also very useful when going through a hash table. Since we won't know the numbers the hash contains, we can simply loop through it.

Thanks.