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FileStream to Bitmap - Parameter is not valid

I have read the posts on this subject but none of them explains it to me clearly enough to be able to fix the problem.
I am trying to upload a file from a local directory to the server.
Here is my code:
string fullPath = Path.Combine(
AppDomain.CurrentDomain.BaseDirectory + #"Images\Readings", PhotoFileName);
Stream s = System.IO.File.OpenRead(fileUpload);
byte[] buffer = new byte[s.Length];
s.Read(buffer, 0, Convert.ToInt32(s.Length));
using (FileStream fs = new FileStream(fullPath, FileMode.Create))
{
fs.Write(buffer, 0, Convert.ToInt32(fs.Length));
Bitmap bmp = new Bitmap((Stream)fs);
bmp.Save(fs, ImageFormat.Jpeg);
}
I keep on getting an Argument Exception: "Parameter is not valid" on line:
Bitmap bmp = new Bitmap((Stream)fs);
Can anyone explain this to me please

There are at least two problems, probably three. First, your copying code is broken:
byte[] buffer = new byte[s.Length];
s.Read(buffer, 0, Convert.ToInt32(s.Length));
You've assumed that this will read all of the data in a single Read call, and ignored the return value for Read. Generally, you'd need to loop round, reading data and writing it (the amount you've just read) to the output stream, until you read the end. However, as of .NET 4, Stream.CopyTo makes this much simpler.
Next is how you're creating the bitmap:
using (FileStream fs = new FileStream(fullPath, FileMode.Create))
{
fs.Write(buffer, 0, Convert.ToInt32(fs.Length));
Bitmap bmp = new Bitmap((Stream)fs);
bmp.Save(fs, ImageFormat.Jpeg);
}
You're trying to read from the stream when you've just written to it - but without "rewinding"... so there's no more data left to read.
Finally, I would strongly advise against using Bitmap.Save to write to the same stream that you're loading the bitmap from. Bitmap will keep a stream open, and read from it when it needs to - if you're trying to write to it at the same time, that could be very confusing.
It's not clear why you're using Bitmap at all, to be honest - if you're just trying to save the file that was uploaded, without any changes, just use:
using (Stream input = File.OpenRead(fileUpload),
output = File.Create(fullPath))
{
input.CopyTo(output);
}
This is assuming that fileUpload really is an appropriate filename - it's not clear why you haven't just written the file to the place you want to write it to straight away, to be honest. Or use File.Copy to copy the file. The above code should work with any stream, so you can change it to save the stream straight from the request...

How to save FileSteam as PDF file

I am using a third party tool to get the scanned content from the scanner. On button click it executes the code and gives the content as a FileStream. Now I need to save this FileStream content as a pdf file in to a specified folder.
After saving I need to open the file in browser. How can I save the FileStream as a PDF file?

You can write the stream directly to the output buffer of the response.
So if you're at the point in your code where you have the filestream from the scanner. Simply read bytes from the scanner filestream and write them to the Response.OutputStream
Set the contentType to application/pdf
Make sure you return nothing else. The users browser will do whatever it is configured to do now, either save to disk or show in the browser. You can also save to disk on the server at this point as well in case you wanted a backup.
I'm assuming your file stream is already a pdf, otherwise you'll need to use something like itextsharp to create the pdf.
Edit
Here's some rough and ready code to do it. You'll want to tidy this up, like adding exception trapping to make sure the file stream gets cleaned up properly.
public void SaveToOutput(Stream dataStream)
{
dataStream.Seek(0, SeekOrigin.Begin);
FileStream fileout = File.Create("somepath/file.pdf");
const int chunk = 512;
byte[] buffer = new byte[512];
int bytesread = dataStream.Read(buffer,0,chunk);
while (bytesread == chunk)
{
HttpContext.Current.Response.OutputStream.Write(buffer, 0, chunk);
fileout.Write(buffer, 0, chunk);
bytesread = dataStream.Read(buffer, 0, chunk);
}
HttpContext.Current.Response.OutputStream.Write(buffer, 0, bytesread);
fileout.Write(buffer, 0, bytesread);
fileout.Close();
HttpContext.Current.Response.ContentType = "application/pdf";
}
Simon

You might want to take a look at the C# PDF Library on SourceForge: http://sourceforge.net/projects/pdflibrary/

If I'm understanding you correctly, the third party library is handing you a stream containing the data for the scanned document and you need to write it to a file? If that's the case you need to look up file I/O in C#. Here's a link and an example:
Stream sourceStream = scanner.GetOutput(); // whereever the source stream is
FileStream targetStream = File.OpenWrite(filename, FileMode.Create());
int bytesRead = 0;
byte[] buffer = new byte[2048];
while (true) {
bytesRead = sourceStream.Read(buffer, 0, buffer.length);
if (bytesRead == 0)
break;
targetStream.Write(buffer, 0, bytesRead);
}
sourceStream.Close();
targetStream.Close();

not sure, but maybe check this
http://sourceforge.net/projects/itextsharp/
iTextSharp + FileStream = Corrupt PDF file

Another prominent PDF library (which I have used in the past as well) is iTextSharp. You can take a look at this tutorial on how to convert your Stream to PDF then have the user download it.

FileUpload to FileStream

I am in process of sending the file along with HttpWebRequest. My file will be from FileUpload UI. Here I need to convert the File Upload to filestream to send the stream along with HttpWebRequest. How do I convert the FileUpload to a filestream?

Since FileUpload.PostedFile.InputStream gives me Stream, I used the following code to convert it to byte array
public static byte[] ReadFully(Stream input)
{
byte[] buffer = new byte[input.Length];
//byte[] buffer = new byte[16 * 1024];
using (MemoryStream ms = new MemoryStream())
{
int read;
while ((read = input.Read(buffer, 0, buffer.Length)) > 0)
{
ms.Write(buffer, 0, read);
}
return ms.ToArray();
}
}

Might be better to pipe the input stream directly to the output stream:
inputStream.CopyTo(outputStream);
This way, you are not caching the entire file in memory before re-transmission. For example, here is how you would write it to a FileStream:
FileUpload fu; // Get the FileUpload object.
using (FileStream fs = File.OpenWrite("file.dat"))
{
fu.PostedFile.InputStream.CopyTo(fs);
fs.Flush();
}
If you wanted to write it directly to another web request, you could do the following:
FileUpload fu; // Get the FileUpload object for the current connection here.
HttpWebRequest hr; // Set up your outgoing connection here.
using (Stream s = hr.GetRequestStream())
{
fu.PostedFile.InputStream.CopyTo(s);
s.Flush();
}
That will be more efficient, as you will be directly streaming the input file to the destination host, without first caching in memory or on disk.

You can't convert a FileUpload into a FileStream. You can, however, get a MemoryStream from that FileUpload's PostedFile property. You can then use that MemoryStream to fill your HttpWebRequest.

You can put a FileUpload file directly into a MemoryStream by using FileBytes (simplified answer from Tech Jerk)
using (MemoryStream ms = new MemoryStream(FileUpload1.FileBytes))
{
//do stuff
}
Or if you do not need a memoryStream
byte[] bin = FileUpload1.FileBytes;

convert base64Binary to pdf

I have raw data of base64Binary.
string base64BinaryStr = "J9JbWFnZ......"
How can I make pdf file? I know it need some conversion. Please help me.

Step 1 is converting from your base64 string to a byte array:
byte[] bytes = Convert.FromBase64String(base64BinaryStr);
Step 2 is saving the byte array to disk:
System.IO.FileStream stream =
new FileStream(#"C:\file.pdf", FileMode.CreateNew);
System.IO.BinaryWriter writer =
new BinaryWriter(stream);
writer.Write(bytes, 0, bytes.Length);
writer.Close();

using (System.IO.FileStream stream = System.IO.File.Create("c:\\temp\\file.pdf"))
{
System.Byte[] byteArray = System.Convert.FromBase64String(base64BinaryStr);
stream.Write(byteArray, 0, byteArray.Length);
}

First convert the Bas64 string to byte[] and write it into a file.
byte[] bytes = Convert.FromBase64String(base64BinaryStr);
File.WriteAllBytes(#"FolderPath\pdfFileName.pdf", bytes );

This code does not write any file on the hard drive.
Response.AddHeader("Content-Type", "application/pdf");
Response.AddHeader("Content-Length", base64Result.Length.ToString());
Response.AddHeader("Content-Disposition", "inline;");
Response.AddHeader("Cache-Control", "private, max-age=0, must-revalidate");
Response.AddHeader("Pragma", "public");
Response.BinaryWrite(Convert.FromBase64String(base64Result));
Note: the variable base64Result contains the Base64-String: "JVBERi0xLjMgCiXi48/TIAoxI..."

All you need to do is run it through any Base64 decoder which will take your data as a string and pass back an array of bytes. Then, simply write that file out with pdf in the file name.
Or, if you are streaming this back to a browser, simple write the bytes to the output stream, marking the appropriate mime-type in the headers.
Most languages either have built in methods for converted to/from Base64. Or a simple Google with your specific language will return numerous implementations you can use. The process of going back and forth to Base64 is pretty straightforward and can be implemented by even novice developers.

base64BinaryStr - from webservice SOAP message
byte[] bytes = Convert.FromBase64String(base64BinaryStr);

Delete dynamically generated PDF file immediately after it has been displayed to user

I'm creating a PDF file on the fly using ITextSharp and ASP.NET 1.1. My process is as follows -
Create file on server
Redirect browser to newly created PDF
file so it is displayed to user
What I'd like to do is delete the PDF from the server as soon it is displayed in the users browser. The PDF file is large so it is not an option to hold it in memory, an initial write to the server is required. I'm currently using a solution that periodically polls for files then deletes them, but I'd prefer a solution that deletes the file immediately after it has been downloaded to the client machine. Is there a way to do this?

Instead of redirecting the browser to the created file you could serve the file yourself using you own HttpHandler. Then you could delete the file immediately after you served it or you could even create the file in memory.
Write the PDF file directly to the Client:
public class MyHandler : IHttpHandler {
public void ProcessRequest(System.Web.HttpContext context) {
context.Response.ContentType = "application/pdf";
// ...
PdfWriter.getInstance(document, context.Response.OutputStream);
// ...
or read an already generated file 'filename', serve the file, delete it:
context.Response.Buffer = false;
context.Response.BufferOutput = false;
context.Response.ContentType = "application/pdf";
Stream outstream = context.Response.OutputStream;
FileStream instream =
new FileStream(filename, FileMode.Open, FileAccess.Read, FileShare.Read);
byte[] buffer = new byte[BUFFER_SIZE];
int len;
while ((len = instream.Read(buffer, 0, BUFFER_SIZE)) > 0) {
outstream.Write(buffer, 0, len);
}
outstream.Flush();
instream.Close();
// served the file -> now delete it
File.Delete(filename);
I didn't try this code. This is just how I think it would work ...

Inspired by f3lix's answer (thanks f3lix!) I've come up with the folowing VB.net code -
HttpContext.Current.Response.ClearContent()
HttpContext.Current.Response.ClearHeaders()
HttpContext.Current.Response.ContentType = "application/pdf"
HttpContext.Current.Response.TransmitFile(PDFFileName)
HttpContext.Current.Response.Flush()
HttpContext.Current.Response.Close()
File.Delete(PDFFileName)
This appears to work - is the 'WriteFile' method I've used any less efficent that the stream methods used by f3lix? Is there a method available that's more efficient than either of our solutions?
EDIT (19/03/2009) Based on comments below I've changed 'WriteFile' method to 'TransmitFile' as it appears it sends the file down to client in chunks rather than writing the entire file to the webserver's memory before sending. Further info can be found here.

Or you could just return it to the browser without writing to disk at all:
byte[] pdf;
using (MemoryStream ms = new MemoryStream()) {
Document doc = new Document();
PdfWriter.GetInstance(doc, ms);
doc.AddTitle("Document Title");
doc.Open();
doc.Add(new Paragraph("My paragraph."));
doc.Close();
pdf = ms.GetBuffer();
}
Response.ContentType = "application/pdf";
Response.AddHeader("Content-Disposition", "attachment;filename=MyDocument.pdf");
Response.OutputStream.Write(pdf, 0, pdf.Length);

The solution:
Response.TransmitFile(PDFFileName)
Response.Flush()
Response.Close()
File.Delete(PDFFileName)
Simply doesn't work for me (file never makes it to client). Reading in a byte array and calling Response.BinaryWrite isn't an option either since the file may be large. Is the only hack for this to start an asynchronous process that waits for the file to be released and then delete it?