How do I compare the fields/properties between POCOs? [duplicate]

Question

Possible Duplicate:
Comparing object properties in c#

Let's say I have a POCO:

public class Person
{
    public string Name { get; set; }
    public DateTime DateOfBirth { get; set; }
    public IList<Person> Relatives { get; set; }
}

I want to compare two instances of Person to see if they're equal to each other. Naturally, I would compare Name, DateOfBirth, and the Relatives collection to see if they're equal. However, this would involve me overriding Equals() for each POCO and manually writing the comparison for each field.

My question is, how can I write a generic version of this so I don't have to do it for each POCO?

Answer 1

If you are not worried about performance, you could use reflection in a utility function to iterate over each field and compare their values.

using System; 
using System.Reflection; 


public static class ObjectHelper<t> 
{ 
    public static int Compare(T x, T y) 
    { 
        Type type = typeof(T); 
        var publicBinding = BindingFlags.DeclaredOnly | BindingFlags.Public;
        PropertyInfo[] properties = type.GetProperties(publicBinding); 
        FieldInfo[] fields = type.GetFields(publicBinding); 
        int compareValue = 0; 


        foreach (PropertyInfo property in properties) 
        { 
            IComparable valx = property.GetValue(x, null) as IComparable; 
            if (valx == null) 
                continue; 
            object valy = property.GetValue(y, null); 
            compareValue = valx.CompareTo(valy); 
            if (compareValue != 0) 
                return compareValue; 
        } 
        foreach (FieldInfo field in fields) 
        { 
            IComparable valx = field.GetValue(x) as IComparable; 
            if (valx == null) 
                continue; 
            object valy = field.GetValue(y); 
            compareValue = valx.CompareTo(valy); 
            if (compareValue != 0) 
                return compareValue; 
        } 
    return compareValue; 
    } 
}