How to get default content type of list programmatically

Question

How can I get default content type of sharepoint list programmatically?

Answer 1

SPContentType defaultCT = list.ContentTypes[0];

This should get you the first content type which is the default one.

Answer 2

You can run the following to determine the content type ordering (first is default).

SPList list = (code to identify your list instance here);
var listFolder = list.RootFolder;
var contentTypeOrder listFolder.UniqueContentTypeOrder;
var defaultContentType = contentTypeOrder[0];

The defaultContentType variable will then contain the default content type object.