在a标签href属性直接写文件地址有些文件不会进入下载(例如 图片类型)，浏览器会自动打开预览

这时可以使用下面这种方式进行文件下载

 Html代码

点击下载

C#代码

/// 
        /// 文件下载        /// 
        /// 文件名(下载后的名字)        /// 文件路径        public void DownloadFile(string fileName, string path)        {            HttpContext.Response.ContentType = "application/ms-download";            string s_path = path;            WebClient wc = new WebClient();            wc.Encoding = Encoding.UTF8;            byte[] temp_byte = wc.DownloadData(s_path);            HttpContext.Response.Clear();            HttpContext.Response.AddHeader("Content-Type", "application/octet-stream");            HttpContext.Response.Charset = "utf-8";            HttpContext.Response.AddHeader("Content-Disposition", "attachment;filename=" + fileName);            HttpContext.Response.AddHeader("Content-Length", temp_byte.Length.ToString());            HttpContext.Response.BinaryWrite(temp_byte);            HttpContext.Response.Flush();            HttpContext.Response.Clear();            HttpContext.Response.End();        }