NativeScript IOS retrive Image URL from PHAsset objects

How can I get/build image URL from PHAsset objects? I want to get the full path so that I can show the image in view or upload it in remote server. I tried like this:

let data = NSMutableArray.arrayWithArray(assets);
let val = data.objectAtIndex(0);

I am getting the value like this:

burstIdentifier: null
    burstSelectionTypes: 0
    creationDate: Thu Aug 09 2012 02:52:11 GMT+0800 (CST)
    duration: 0
    favorite: false
    hidden: false
    mediaSubtypes: 0
    mediaType: 1
    pixelHeight: 2002
    pixelWidth: 3000
    representsBurst: false
    sourceType: 1
    localIdentifier: 9F983DBA-EC35-42B8-8773-B597CF782EDD/L0/001

But how can I build complete URL? Thanks in advance.