How to open a file from Memory Stream

Question

Is it possible to open a file directly from a MemoryStream opposed to writing to disk and doing Process.Start() ? Specifically a pdf file? If not, I guess I need to write the MemoryStream to disk (which is kind of annoying). Could someone then point me to a resource about how to write a MemoryStream to Disk?

Solution 1

It depends on the client :) if the client will accept input from stdin you could push the dta to the client. Another possibility might be to write a named-pipes server or a socket-server - not trivial, but it may work.

However, the simplest option is to just grab a temp file and write to that (and delete afterwards).

var file = Path.GetTempFileName();
using(var fileStream = File.OpenWrite(file))
{
    var buffer = memStream.GetBuffer();
    fileStream.Write(buffer, 0, (int)memStream.Length);
}

Remember to clean up the file when you are done.

Solution 2

Path.GetTempFileName() returns file name with '.tmp' extension, therefore you cant't use Process.Start() that needs windows file association via extension.

Comments

[Marc Gravell]

(James - I removed the 4.0 dependency from my answer)

[Magnus]

Or use WriteTo (for non 4.0)

[Marc Gravell]

@Magnus - I removed that; realised that I can use the back-buffer from MemoryStream