private async void button3_Click(object sender, EventArgs e) { var MediaManagerDataJSON = File.ReadAllText(@"D:\wamp\tmp\media_manager_posts.json"); var PublishedPostsDataJSON = File.ReadAllText(@"D:\wamp\tmp\published_posts_graphAPI.json"); var MediaManagerData = Newtonsoft.Json.JsonConvert.DeserializeObject <List <MediaManagerPostModels.Datum> >(MediaManagerDataJSON); var PublishedPostsData = Newtonsoft.Json.JsonConvert.DeserializeObject <List <PublishedPostsGraphModels.Datum> >(PublishedPostsDataJSON); // match each article from media manager list with a data_link from published posts list. foreach (var article in MediaManagerData) { // PublishedPosts data list contains IDs with prefix, so split them first and get the actual id var ppEntry = PublishedPostsData.FirstOrDefault(a => a.id.Split('_')[1].Equals(article.id)); if (ppEntry != null && ppEntry.attachments != null) { article.data_link = ppEntry.attachments.data[0].unshimmed_url; } } await MongoDBHandler.InsertFbGraphArticles(MediaManagerData); }