C#匯出pdf的實現方法（瀏覽器不預覽直接下載）
阿新 • • 發佈：2020-01-07
前言
這篇文章主要給大家介紹了關於C#匯出pdf的實現方法，分享出來供大家參考學習，下面話不多說了，來一起看看詳細的介紹吧
方法如下：
一.介面部分的程式碼
[HttpGet]
public HttpResponseMessage ExportPdf(string id)
{
string pdfName = "";
//id 查詢條件，根據實際情況修改即可
//pdfName 例如download.pdf
byte[] pdfData= _policyGapManagerService.ExportPdf(id,out pdfName);//獲得pdf位元組
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陣列
1.下載http模式的pdf檔案（以ASP.NET為例，將PDF存在專案的目錄下，可以通過http直接開啟專案下的pdf檔案）
#region 呼叫本地檔案使用返回pdfbyte陣列
/// <summary>
/// 呼叫本地檔案使用返回pdfbyte陣列
/// </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,hebyte.Length);
return hebyte;
}
}
#endregion 呼叫本地檔案使用返回pdfbyte陣列
#region 從網站上下載pdf，轉化為位元組流
/// <summary>
/// 從網站上下載pdf，轉化為位元組流
/// </summary>
/// <param name="srcPdfFile">檔案地址：'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();
//讀取到記憶體
MemoryStream stmMemory = new MemoryStream();
byte[] buffer1 = new byte[length];
int i;
//將位元組逐個放入到Byte 中
while ((i = stream.Read(buffer1,buffer1.Length)) > 0)
{
stmMemory.Write(buffer1,i);
}
arraryByte = stmMemory.ToArray();
stmMemory.Close();
}
return arraryByte;
}
#endregion 從網站上下載pdf，轉化為位元組流
#region 從網站上下載檔案，儲存到其他路徑
/// <summary>
/// 從網站上下載檔案，儲存到其他路徑
/// </summary>
/// <param name="pdfFile">檔案地址</param>
/// <param name="saveLoadFile">儲存檔案路徑：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);
//建立一個ＷＥＢ請求，返回HttpWebRequest物件
HttpWebRequest hwr = (HttpWebRequest)WebRequest.Create(downUri);
//流物件使用完後自動關閉
using (Stream stream = hwr.GetResponse().GetResponseStream())
{
//檔案流，流資訊讀到檔案流中，讀完關閉
using (FileStream fs = File.Create(f))
{
//建立位元組組，並設定它的大小是多少位元組
byte[] bytes = new byte[102400];
int n = 1;
while (n > 0)
{
//一次從流中讀多少位元組，並把值賦給Ｎ，當讀完後，Ｎ為０,並退出迴圈
n = stream.Read(bytes,10240);
fs.Write(bytes,n); //將指定位元組的流資訊寫入檔案流中
}
}
}
//return flag;
//return _outPath + saveLoadFile;
return f;
}
#endregion 從網站上下載檔案，儲存到其他路徑2.ftp模式的pdf檔案
/// <summary>
/// 下載FTP檔案。
/// </summary>
/// <param name="offsetPath">相對路徑</param>
/// <param name="fileName">檔名稱</param>
/// <returns>下載結果，本地檔案路徑</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 "檔案不存在!"; }
int readCout = 0;
byte[] bytes = new byte[1024];
readCout = s.Read(bytes,1024);
while (readCout > 0)
{
fs.Write(bytes,readCout);
readCout = s.Read(bytes,1024);
}
}
}
resp.Close();
return _outPath + fileName;
}
catch (Exception e)
{
return e.Message;
}
}
/// <summary>
/// 判斷檔案是否存在
/// </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>
/// 獲取目錄下所有檔案
/// </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;
}
}總結
以上就是這篇文章的全部內容了，希望本文的內容對大家的學習或者工作具有一定的參考學習價值，謝謝大家對我們的支援。