CODEWITHSUNDEEP
c#asp.netsql
atrljoe
atrljoe

Reputation: 8151

Download PDF File From DB to Local Server for Download

I am trying to figure out how to get a file that I have stored in my Database, onto the filesystem. I have looked everywhere, but all I can find is like for images pulling them out and serving them via Response. Can anyone point me in the direction of a tutorial or provide me with some input on which way to go?

Upvotes: 0

Views: 576

Answers (2)

David
David

Reputation: 218837

From the perspective of serving the file through the web, the process is exactly the same for images as it is for any file type. The only difference would be the content type in the response header. (For a PDF, it would be application/pdf.)

Understand that over HTTP there is absolutely no concept of "files." All you have are requests and responses, each of which has headers and data. Whether it's an image, a PDF, a web page, anything... the structure of the response being delivered to the client (browser) is exactly the same. Headers tell the browser what kind of data it is and various other meta-details about it, and the data is just the raw data of the "file" being sent. The browser can choose what to do with the data.

In the case of web pages, the browser generally just renders it. In the case of other or unknown content types, the browser generally prompts the user to save it as a file. (Note that a file name can also be suggested in the header of the response.)

Edit: In response to your comment on @Pete M's answer...

The process is still very similar. "Files" as email attachments work in much the same way as "files" over HTTP. Essentially, all you need is the data stream and the content type. When building the MailMessage object, take a look at the Attachment object. As you pull your PDF file from the database (just like when pulling images from the database to serve to a browser client), set the data stream to the ContentStream on the attachment object. Then also set the ContentType (again, application/pdf) and the Name on the attachment object and you should be able to send it as part of the MailMessage.

You may need to set more options on the Attachment as well. Testing will indicate how explicit you need to be with things like encoding. If you can share some code as you attempt this, we can help you with that code.

Upvotes: 1

Pete M
Pete M

Reputation: 2048

It's no different than writing out any other kind of file. If you find a good "read/write text file" tutorial it's going to be the exact same process, you'll just get your initial stream from the database.

Can I ask why you are doing this? If it's for caching so you can return it to users who ask for it I would consider other options first. Requiring a dip into disk will often cause a bottle neck in performance.

Upvotes: 0

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