How to implement SOLID principles into an existing project

Question

I apologize for the subjectiveness of this question, but I am a little stuck and I would appreciate some guidance and advice from anyone who\'s had to deal with this issue b

Answer 1

It will be a time consuming process. You need to read the code and identify parts that do not meet the SOLID principles and refactor into new classes. Using a VS add-in like Resharper (http://www.jetbrains.com) will assist with the refactoring process.

Ideally you will have good coverage of automated unit tests so that you can ensure your changes do not introduce problems with the code.

More Information

In the main API class, you need to identify methods that relate to each other and create a class that more specifically represents what actions the method performs.

e.g.

Let's say I had an Address class with separate variables containing street number, name, etc. This class is responsible for inserting, updating, deleting, etc. If I also needed to format an address a specific way for a postal address, I could have a method called GetFormattedPostalAddress() that returned the formatted address.

Alternatively, I could refactor this method into a class called AddressFormatter that takes an Address in it constructor and has a Get property called PostalAddress that returns the formatted address.

The idea is to separate different responsibilities into separate classes.