C# Data Validation Design Patterns
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I have a bunch of data classes in my C# project. I need to perform a validation before the processing of the objects of those classes. The classes donot have a common interface.
I am trying to formulate some sort of design pattern where I can specify the validations that need to be performed on each field of the class; without having a set of if else type conditions. 

I came across the specification pattern, but that did not seem very convincing.

Are there any existing patterns/C# methodologies that I can use?




