ModelState plays an important role in client-side validation with ASP.NET MVC. Today I wanted to validate my model on server side and prepare a list of errors based on this validation.

I was able to do this using a little LINQ,

public static List<string> GetErrorListFromModelState(ModelStateDictionary modelState)  
{  
var query = from state in modelState.Values  
from error in state.Errors  
select error.ErrorMessage;

var errorList = query.ToList();  
return errorList;  
}

The above method returns a list of validation errors. Hope this helps :)

Further Reading :

How to get all Errors from asp.net mvc modelState?

How do I get the collection of Model State Errors in ASP.NET MVC?