C#•3y ago

✅ Converting value to nullable

I've got a point in my code where I've got:

int intValue = 5;
object? value = intValue; // contains a non-nullable value, an int, float, etc
Type type = typeof(int?);

value = ChangeType(value, type);

int intValue = 5;
object? value = intValue; // contains a non-nullable value, an int, float, etc
Type type = typeof(int?);

value = ChangeType(value, type);

I need to write

ChangeType

ChangeType

, and only have access to

value

value

and

type

type

. Using

Convert.ChangeType()

Convert.ChangeType()

doesn't work here, and throws an exception.

How can I convert this value to nullable successfully?

Thanks

Aaron•4/5/23, 1:08 PM

you can't

Aaron•4/5/23, 1:08 PM

you can never have a boxed nullable

HughOP•4/5/23, 1:08 PM

ahh shit...

HughOP•4/5/23, 1:08 PM

okay

Pobiega•4/5/23, 1:09 PM

PPobiega ```cs int val = 123; object? nullable = new int?(val); ``` ?

HughOP•4/5/23, 1:09 PM

I don't know that it's int at that point

Aaron•4/5/23, 1:09 PM

that just gets boxed as an int

HughOP•4/5/23, 1:09 PM

I can re-work some other code further up the chain to make this work

Aaron•4/5/23, 1:09 PM

if the Nullable has no value, when you box it, it gives you a literal null

Pobiega•4/5/23, 1:09 PM

I'm not sure what the goal here is

MODiX•4/5/23, 1:10 PM

Windows10CE#8553

REPL Result: Success

Result: bool

Compile: 493.959ms | Execution: 36.655ms | React with ❌ to remove this embed.

HughOP•4/5/23, 1:10 PM

If this isn't possible, then I've got another approach that I can try here

HughOP•4/5/23, 1:10 PM

Thanks both