How much work should the constructor for an HTML parsing class do?

Question

How much work is it reasonable for an object constructor to do? Should it simply initialize fields and not actually perform any operations on data, or is it okay to have it

Answer 1

As quite a few have commented the general rule is to only do initialization in constructors and never use say virtual methods (you will get a compiler warning if you try pay attention to that warning :) ). In you specific case I wouldn't go for the parHTML method either. an object should be in a valid state when it's constructed you should have to do stuff to the object before you can really use it.

Personally I'd go for a factory method. Exposing a class with no public constructors and create it using a factory method instead. Let you're factory method do the parsing and pass the parsed result to a private/protected constructor.

take a look at System.Web.WebRequest if you wanna see a sample of some similiar logic.