.NET - Get default value for a reflected PropertyInfo

Question

This is really stumping me today. I\'m sure its not that hard, but I have a System.Reflection.PropertyInfo object. I want to set its value based on the result of a database

Answer 1

This is a more polished version that maintains the .NET Runtime's functionality without adding any unnecessary custom code.

NOTE: This code written for .NET 3.5 SP1

namespace System {

public static class TypedDefaultExtensions {

    public static object ToDefault(this Type targetType) {

        if (targetType == null)
            throw new NullReferenceException();

        var mi = typeof(TypedDefaultExtensions)
            .GetMethod("_ToDefaultHelper", Reflection.BindingFlags.Static | Reflection.BindingFlags.NonPublic);

        var generic = mi.MakeGenericMethod(targetType);

        var returnValue = generic.Invoke(null, new object[0]);
        return returnValue;
    }

    static T _ToDefaultHelper() {
        return default(T);
    }
}

}

USAGE:

PropertyInfo pi; // set to some property info
object defaultValue = pi.PropertyType.ToDefault();

public struct MyTypeValue { public int SomeIntProperty { get; set; }
var reflectedType = typeof(MyTypeValue);
object defaultValue2 = reflectedType.ToDefault();

Rashad Rivera (OmegusPrime.com)