GetExtension should return null in case it didn't find the extension

[HunteRoi]

This is not "mandatory" but would lead to a more friendly approach for a new user that comes across your package. Obviously, if the data is not found, you should never return a value (even if an empty string) as it may lead to strange behavior or misunderstanding.

I would highly recommend to introduce this breaking change in your library:

public static string GetExtension(string mimeType, bool throwErrorIfNotFound = true)
{
     ...

-    return string.Empty;
+    return null;
}

[HunteRoi]

In addition to this, I would recommend anyone making checks against a string to use the extension methods provided to that use:

• String.IsNullOrEmpty(String)
• String.IsNullOrWhiteSpace(String)

[samuelneff]

I'm not going to introduce what could easily be a breaking change for everybody. Sorry. We are introducing a TryGetExtension method in another PR which should satisfy your needs.

[HunteRoi]

Can you link that pull request ? I'd like to take a look at the code. I don't see anything related to that but it's a good idea to introduce a TryGetExtension too!

[samuelneff]

It's now been merged. Take a look at the updated code that includes TryGetExtension. NuGet also updated.