C# 导出pdf(浏览器不预览直接下载)

一.接口部分的代码

[HttpGet]        public HttpResponseMessage ExportPdf(string id)        {            string pdfName = "";       //id 查询条件,根据实际情况修改即可       //pdfName 例如download.pdf            byte[] pdfData= _policyGapManagerService.ExportPdf(id, out pdfName);//获得pdf字节            var result = new HttpResponseMessage(HttpStatusCode.OK)            {                Content = new ByteArrayContent(pdfData)            };            result.Content.Headers.ContentDisposition =                new ContentDispositionHeaderValue("attachment")                {                    FileName = pdfName                };            result.Content.Headers.ContentType =new MediaTypeHeaderValue("application/pdf");            return result;        }

二.返回pdfbyte数组

1.下载http模式的pdf文件(以ASP.NET为例,将PDF存在项目的目录下,可以通过http直接打开项目下的pdf文件)

#region 调用本地文件使用返回pdfbyte数组        /// <summary>        /// 调用本地文件使用返回pdfbyte数组        /// </summary>        /// <param name="srcPdfFile">'D:\in2434341555551.pdf’</param>        /// <returns></returns>        public static byte[] GetSignaturePDFByte(string srcPdfFile)        {            using (FileStream fsRead = new FileStream(srcPdfFile, FileMode.Open, FileAccess.Read, FileShare.Read))            {                int fsLen = (int)fsRead.Length;                byte[] hebyte = new byte[fsLen];                fsRead.Read(hebyte, 0, hebyte.Length);                return hebyte;            }        }        #endregion 调用本地文件使用返回pdfbyte数组        #region 从网站上下载pdf,转化为字节流        /// <summary>        /// 从网站上下载pdf,转化为字节流        /// </summary>        /// <param name="srcPdfFile">文件地址:'https://******/group2/M00/00/04/wKj-mlpcoZ2IUbK5AACrpaV6k98AAAB6gAAAAAAAKu9562.pdf'</param>        /// <returns></returns>        public static Byte[] GetByteByRemoteURL(string srcPdfFile)        {            byte[] arraryByte;            HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create(srcPdfFile);            req.Method = "GET";            using (WebResponse wr = req.GetResponse())            {                StreamReader responseStream = new StreamReader(wr.GetResponseStream(), Encoding.UTF8);                int length = (int)wr.ContentLength;                byte[] bs = new byte[length];                HttpWebResponse response = wr as HttpWebResponse;                Stream stream = response.GetResponseStream();                //读取到内存                MemoryStream stmMemory = new MemoryStream();                byte[] buffer1 = new byte[length];                int i;                //将字节逐个放入到Byte 中                while ((i = stream.Read(buffer1, 0, buffer1.Length)) > 0)                {                    stmMemory.Write(buffer1, 0, i);                }                arraryByte = stmMemory.ToArray();                stmMemory.Close();            }            return arraryByte;        }        #endregion 从网站上下载pdf,转化为字节流        #region 从网站上下载文件,保存到其他路径        /// <summary>        /// 从网站上下载文件,保存到其他路径        /// </summary>        /// <param name="pdfFile">文件地址</param>        /// <param name="saveLoadFile">保存文件路径:D:\12221.pdf</param>        /// <returns></returns>        public string SaveRemoteFile( string saveLoadFile , string pdfFile)        {            //bool flag = false;            var f = saveLoadFile + Guid.NewGuid().ToString("D") + ".pdf";            Uri downUri = new Uri(pdfFile);            //建立一个WEB请求,返回HttpWebRequest对象            HttpWebRequest hwr = (HttpWebRequest)WebRequest.Create(downUri);            //流对象使用完后自动关闭            using (Stream stream = hwr.GetResponse().GetResponseStream())            {                //文件流,流信息读到文件流中,读完关闭                using (FileStream fs = File.Create(f))                {                    //建立字节组,并设置它的大小是多少字节                    byte[] bytes = new byte[102400];                    int n = 1;                    while (n > 0)                    {                        //一次从流中读多少字节,并把值赋给N,当读完后,N为0,并退出循环                        n = stream.Read(bytes, 0, 10240);                        fs.Write(bytes, 0, n); //将指定字节的流信息写入文件流中                    }                }            }            //return flag;            //return _outPath + saveLoadFile;            return f;        }        #endregion 从网站上下载文件,保存到其他路径

2.ftp模式的pdf文件

/// <summary>        /// 下载FTP文件。        /// </summary>        /// <param name="offsetPath">相对路径</param>        /// <param name="fileName">文件名称</param>        /// <returns>下载结果,本地文件路径</returns>        public string DownLoad(string offsetPath,string fileName)        {            try            {                FtpWebRequest ftpWeb = (FtpWebRequest)WebRequest.Create(_ftpRootPath + offsetPath + fileName);                ftpWeb.Method = WebRequestMethods.Ftp.DownloadFile;                ftpWeb.UseBinary = true;                var resp = ftpWeb.GetResponse();                using (FileStream fs = new FileStream(_outPath + fileName, FileMode.Create))                {                    using (var s = resp.GetResponseStream())                    {                        if (s == null) { return "文件不存在!"; }                        int readCout = 0;                        byte[] bytes = new byte[1024];                        readCout = s.Read(bytes, 0, 1024);                        while (readCout > 0)                        {                            fs.Write(bytes, 0, readCout);                            readCout = s.Read(bytes, 0, 1024);                        }                    }                }                resp.Close();                return _outPath + fileName;            }            catch (Exception e)            {                return e.Message;            }                    }        /// <summary>        /// 判断文件是否存在        /// </summary>        /// <param name="offsetPath"></param>        /// <param name="fileName"></param>        /// <returns></returns>        public bool FileExists(string offsetPath, string fileName)        {            try            {                FtpWebRequest ftpWeb = (FtpWebRequest)WebRequest.Create(_ftpRootPath + offsetPath + fileName);                ftpWeb.Method = WebRequestMethods.Ftp.DownloadFile;                ftpWeb.UseBinary = true;                var resp = (FtpWebResponse)ftpWeb.GetResponse();                resp.Close();                return true;            }            catch (Exception)            {                return false;            }        }        /// <summary>        /// 获取目录下所有文件        /// </summary>        /// <returns></returns>        public string[] Files(string offsetPath)        {            try            {                FtpWebRequest ftpWeb = (FtpWebRequest)WebRequest.Create(_ftpRootPath + offsetPath);                ftpWeb.Method = WebRequestMethods.Ftp.ListDirectory;                Stream stream = ftpWeb.GetResponse().GetResponseStream();                if (stream == null)                {                    return null;                }                List<string> fileList = new List<string>();                using (StreamReader sr = new StreamReader(stream))                {                    StringBuilder sb = new StringBuilder();                    do                    {                        sb.Append(sr.ReadLine());                        if (sb.Length > 0)                        {                            fileList.Add(sb.ToString());                            sb.Clear();                        }                        else                        {                            break;                        }                    } while (true);                }                return fileList.ToArray();            }            catch (Exception)            {                 return null;            }        }
(0)

相关推荐