Get Object or Associative array's length

If you need to find the length of an object, and I mean the number of children of the specified object, use the following function/method:

public static function getLength(o:Object):uint
{
    var len:uint = 0;
    for (var item:* in o)
        if (item != "mx_internal_uid")
            len++;
    return len;
}

 

In Flex there is no method to get the length of an object and if you look at an object or an associative array in debugging mode you’ll that length property is not present or is 0 for associative arrays.

I know that there are different ways of arranging data in indexed array structures to have the length property but sometimes maybe you want to know if the object has at least a child or how many children it has.

There is another issue… some arrays/objects used mostly as data providers do get an internal property called mx_internal_uid, so you may not want to count that as a child:

if (item != "mx_internal_uid")

 

More about mx_internal_uid here (livedocs) and in a future article.

 

转载自 : http://www.flexer.info/2008/07/31/how-to-find-an-objects-length/