A simple dropdown (select) component written in React using JSX. Takes and array of value/label pairs and displays a select. Optionally takes an 'onchange' function as a param. This will be called with details of the old and newly selected values.
When you have a string that ends with a number, this simple regular expression will allow you to increment the number part e.g. take a text field containing "abc15" and increment it by 1 to return "abc16". Similarly, "xyz99" will become "xyz100", etc.
A simple function that uses a regular expression to validate that a string is a valid MongoDB object id (i.e. a 24 character hex string).
More about MongoDB object id format here: http://docs.mongodb.org/manual/reference/object-id/