C#/.NET - Custom Binary File Formats - Where to Start?

Question

I need to be able to store some data in a custom binary file format. I\'ve never designed my own file format before. It needs to be a friendly format for traveling between the C

Answer 1

ASCII chars 0 or 1 each take up several bits (just like any other character), so if you're storing it like that your "binary" file will be several times larger than it should be. At text file of zeros and ones is not exactly a binary file :)

You can use the BinaryWriter to write raw data directly to a file stream. The only part you need to figure out is translating your in-memory format (usually some kind of object graph) into a byte sequence that the BinaryWriter can consume.

However, if your primary interest is portability, I recommend against a binary format at all. XML is precisely designed to solve the portability and interoperability problem. It's verbose and weighty as a file format, but that's the trade-off you make to get those problems solved for you. If a human-readable format is off the table, Marc's answer is the way to go. No need to reinvent the portability wheel!