Question

I have this bit of code

 NullableConverter nullableConverter = new NullableConverter(type);
 Type baseType = nullableConverter.UnderlyingType;
 Object value = Convert.ChangeType(rule.Data, baseType);
 constant = Expression.Constant(value);

In this case type is decimal? but it could be any nullable type.

I need value to be of type decimal?, not type decimal as it currently is. The problem, is that Convert.ChangeType doesn’t work properly with nullable types. So I’m creating a non-nullable first.

How can I convert the string contained in rule.Data to type?

Answer 1

You can’t.

When a nullable struct is boxed in an Object it doesn’t store a boxed nullable struct. If the struct doesn’t have a value it will just box null, and if it has a value it will box the underlying value of the nullable struct.

You would need to not be boxing it for this to even be possible.