/// <summary>

        /// 读取PDF文件

        /// </summary>

        /// <param name="fName">文件名称(可以从其他地方传进来)</param>

        /// <returns></returns>

        public FileStreamResult readPDF(string fName = "111.pdf")

        {

            string dirp = @"放pdf文件的文件夹路径";

            DirectoryInfo mydir = new DirectoryInfo(dirp);

            string pdfSrc = string.Empty;

            foreach (FileSystemInfo fsi in mydir.GetFileSystemInfos())

            {

                if (fsi is FileInfo)

                {

                    FileInfo fi = (FileInfo)fsi;

                    string x = System.IO.Path.GetDirectoryName(fi.FullName);

                    string s = System.IO.Path.GetExtension(fi.FullName);

if (fi.Name == fName)

                    {

                        pdfSrc = dirp + "\\" + fi.Name;//pdf路径

                        　　ViewBag.title = fi.Name;//网页标题

                    　 }

                }

            }

            FileStream fs = new FileStream(pdfSrc, FileMode.Open, FileAccess.Read);

            return File(fs, "application/pdf");

        }