如果我有一个 PDF 文件作为流,如何将其写入响应输出流?
由于您正在使用MVC,最好的方法是使用FileStreamResult
:
return new FileStreamResult(stream, "application/pdf")
{
FileDownloadName = "file.pdf"
};
使用Response.Write
或Response.OutputStream
来操作控制器是不符合惯用方式的,因为已经存在一个ActionResult,没有理由去编写自己的ActionResult。
可以使用以下方法之一:
//assuming you have your FileStream handle already - named fs
byte[] buffer = new byte[4096];
long count = 0;
while ((count = fs.Read(buffer, 0, buffer.Length)) > 0)
{
response.OutputStream.Write(buffer, 0, count);
response.Flush();
}
您还可以使用 GZIP 压缩以加快文件传输到客户端的速度(流式传输的字节数更少)。
Dim MyFileStream As FileStream
Dim FileSize As Long
MyFileStream = New FileStream(filePath, FileMode.Open)
FileSize = MyFileStream.Length
Dim Buffer(CInt(FileSize)) As Byte
MyFileStream.Read(Buffer, 0, CInt(FileSize))
MyFileStream.Close()
Response.ContentType = "application/pdf"
Response.OutputStream.Write(Buffer, 0, FileSize)
Response.Flush()
Response.Close()
CopyStream(pdfStream, response.OutputStream);
如需实现CopyStream
,请参考在C#中在两个流实例之间复制的最佳方法
protected void Page_Load(object sender, EventArgs e) {
Context.Response.Buffer = false;
FileStream inStr = null;
byte[] buffer = new byte[1024];
long byteCount; inStr = File.OpenRead(@"C:\Users\Downloads\sample.pdf");
while ((byteCount = inStr.Read(buffer, 0, buffer.Length)) > 0) {
if (Context.Response.IsClientConnected) {
Context.Response.ContentType = "application/pdf";
Context.Response.OutputStream.Write(buffer, 0, buffer.Length);
Context.Response.Flush();
}
}
}