private void InitializeViewModel(BlogPost blogPost)
 {
     Author = blogPost.Author;
     Title = blogPost.Title;
     Content = blogPost.Content;
     Category = blogPost.Category;
 }
        public BlogPostViewModel(BlogPost blogPost)
        {
            if (blogPost == null) throw new ArgumentNullException(nameof(blogPost));
            this.blogPost = blogPost;

            InitializeViewModel(blogPost);
        }