Re: Dynamically determine and cast type

From WilsonORMapper's QueryHelper class (this supports a ton more
conversions than Convert.ChangeType and goes from object)... Use the
return value in the property SetValue method call.

/// <summary>
/// Convert a value to another type -- supports Nullable types, unlike
Convert.ChangeType.
/// </summary>
/// <param name="value">Value to be converted -- must be a value type.</param>
/// <param name="type">Type to convert value to -- must be a value type.</param>
/// <returns></returns>
static public object ChangeType(object value, Type type)
{
  if (value == null && type.IsGenericType)
    return Activator.CreateInstance(type);

  if (value == null)
    return null;

  if (type == value.GetType())
    return value;

  if (type.IsEnum)
  {
    if (value is string)
      return Enum.Parse (type, value as string); // RTS/GOP
    else
      return Enum.ToObject(type, value);
  }

  if (type.IsGenericType
      && type.GetGenericTypeDefinition().Equals(typeof(Nullable<>)))
    return Convert.ChangeType(value, Nullable.GetUnderlyingType(type));

  if (!type.IsInterface && type.IsGenericType)
  {
    Type innerType = type.GetGenericArguments()[0];
    object innerValue = QueryHelper.ChangeType(value, innerType); // recurse!
    return Activator.CreateInstance(type, new object[] { innerValue });
  }

  if (value is string && type == typeof(Guid))
    return new Guid(value as string);

  if (value is string && type == typeof(Version))
    return new Version(value as string);

  if (value is IConvertible)
    return Convert.ChangeType(value, type);
  else
    return value;
}


-- 
"He uses statistics as a drunken man uses lamp-posts… for support
rather than illumination." Andrew Lang

Marc C. Brooks
http://musingmarc.blogspot.com