reading from file

[Namal via Digitalmars-d-learn]

Hello, comming from C++, I find it hard to remember and 
understand how reading from file should be done in D. Especially 
since I am not very good in functional programming. So I have a 
file which looks like this:

1,2,3,4
5,6,7,8
9,11,11,12

and so on

How could I read it row by row and create an array accordingly 
without reading the comma?