Question

How to concat many (say 500) mp3 files into one file (any type) and then extract any specific file as mp3 format?

Currently I get all the files using this code:

int i = 0;
string[] files = new string[500];
foreach (var path in Directory.GetFiles(@"R:\abc\a\"))
{
    files[i++] = path;
}

Thanks in advance.

Update: If I can’t extract any specific mp3 file then I want to extract all the mp3 files to a specified directory. ZIP, RAR etc aren’t enough because I have to prevent humans to extract mp3 files without my program.

Answer 1

While a home-brewed container format (such as those suggested in other answers here) might work, I recommend using a well-known container format such as .zip. Although you wouldn’t get much benefit out of compression, you’ll get the file name, plus the ability for other progs to create/extract your file archive.

If you need help on how to create .zip programmatically, research the web (and particularly StackOverflow), and if you still don’t know, ask as a separate question.