How to hide a Model class field based on custom logic in MVC Web Api RC
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I am using Asp.Net Mvc Web api RC. 

I wanted to hide the fields/properties of my model class using custom attribute. Below is my class:

    public class Employee
    {              
         public int EmpId { get; set; }       
         public string Name{ get; set; }
            
         //Wanted to hide this attribute based on custom logic. Like for a certain role, i want to hide the designation
         public string Designation{ get; set; }
            
         public string Department{ get; set; }
    }

How can we achieve using Data Annotations. I mean i wanted to create a separate attribute to use in this manner:

    [HideForRoles(Roles="Admin,Writer")]
    public string Designation{ get; set; }