Fastest way to get an Objects values in as3

问题

Ok, so I swear this question should be all over the place, but its not.

I have a value object, inside are lots of getters/setters. It is not a dynamic class. And I desperately need to search an ArrayCollection filled with them. The search spans all fields, so and there are about 13 different types of VOs I'll be doing this with.

I've tried ObjectUtil.toString() and that works fine and all but it's slow as hell. There are 20 properties to return and ObjectUtil.toString() adds a bunch of junk to the output, not to mention the code is slow to begin with.

flash.utils.describeType() is even worse.

I'll be pleased to hear I'm missing something obvious.

UPDATE: I ended up taking Juan's code along with the filter algorithm I use for searching and created ArrayCollectionX. Which means that every ArrayCollection I use now handles it's own filters. I can search through individual properties of the items in the AC, or with Juan's code it handles full collection search like a champ. There was negligible lag compared to the same solution with external filters.

回答1:

If I understand your problem correctly, what you want is a list of the getters defined for certain objects. As far as I know, you'll have to use describeType for something like this (I'm pretty sure ObjectUtils uses this method under the hood).

Calling describeType a lot is going to be slow, as you note. But for only 13 types, this shouldn't be problematic, I think. Since these types are not dynamic, you know their properties are fixed, so you can retrieve this data once and cache it. You can build your cache up front or as you find new types.

Here's is a simple way to do this in code:

private var typePropertiesCache:Object = {};

private function getPropertyNames(instance:Object):Array {
    var className:String = getQualifiedClassName(instance);
    if(typePropertiesCache[className]) {
        return typePropertiesCache[className];
    }
    var typeDef:XML = describeType(instance);
    var props:Array = [];
    for each(var prop:XML in typeDef.accessor.(@access == "readwrite" || @access == "readonly")) {
        props.push(prop.@name);
    }   
    return typePropertiesCache[className] = props;
}

来源：https://stackoverflow.com/questions/3540003/fastest-way-to-get-an-objects-values-in-as3

标签

apache-flex

actionscript-3

optimization

object

arraycollection