var Id=1; 
var books = (from b in db.Books
                              where b.bookId == Id
                              select new
                              {
                                 //...

                              }).ToList();

var booksId= new list<int>(){ 1 , 2 , 6 , 7}; 
var books = (from b in db.Books
                              where b.bookId == ???
                              select new
                              {
                                 //...

                              }).ToList();

var account = accountList.Items.FirstOrDefault(x => x.Name.ToLowerInvariant().Contains(site));

  $(document).pjax('a[withpjax]', '#pjaxContainer', { timeout: 5000 });

$(document).pjax('a', '#pjaxContainer', { timeout: 5000 });

public class CSS
    {
        public string Color { set; get; }
    }

        public ActionResult GetDynamicStyle()
        {
            var color = "White";
            if (DateTime.Now.Hour > 18 || DateTime.Now.Hour < 8)
            {
                color = "Black";
            }

            this.Response.ContentType = "text/css";
            return PartialView(viewName: "~/Views/Home/_CSS.cshtml", model: new CSS { Color = color });
        }

@model DynamicMvcCSS.Controllers.CSS

.foo {
    color: @Model.Color;
}