Substitution for 'Public Sub New'

In the past, I've created Data access classes with a 'New' Sub (Public Sub New), which returns the connectionstring for the class.

However, somewhere recently I read that (in v2 & above) you can just create a Property with the same name as the class, in order to do this, but I can't find any web page that explains this further.

Can anyone provide any help here?

Also - which method is preferred, as a standard practice now?
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