Basic idea on how to look up a type converter based on a generic type and convert to that value from a string

GenericConverter.cs

public TValue Value<TValue>(string value, TValue defaultValue = default(TValue))
{
  if (string.IsNullOrEmpty(value)) return defaultValue;

  var converter = TypeDescriptor.GetConverter(typeof (TValue));

  return (TValue) converter.ConvertFrom(value);
}