var s = from b in entities.Booklist
                    join c in entities.ChapterInfoList
                    on b.bookid equals c.chapterbookid
                    join d in entities.ChapterContent
                    on c.chapterid equals d.chapterid
                    where b.bookid == bookid && c.chapterindex == chapterindex
                    select new ChapterPageInfo
                    {
                        bookName = b.bookname,
                        bookAuthor = b.bookauthor,
                        dataLength = d.chaptercontent1.Length / 2,
                        content = d.chaptercontent1.Substring(page, pageLength),
                        //ImgFlag =c.imflag,
                        ChapterID = c.chapterid,
                        chapterTitle = c.chaptertitle
                    };

这句查询找不到是什么问题