How to get the pointer of "this" ?

[Vinod K Chandran]

On Monday, 25 May 2020 at 18:42:33 UTC, bauss wrote:
> On Monday, 25 May 2020 at 17:14:13 UTC, Vinod K Chandran wrote:
>> On Monday, 25 May 2020 at 16:54:11 UTC, Mike Parker wrote:
>>> [...]
>>
>> Hi @Mike Parker,
>> Thank you for your valuable suggestions. I will sure follow 
>> them. Well, the  exact line number where the error showing is 
>> the one with the "SetWindowSubclass" function.  In pastebin, 
>> the line number is 124.
>
> Need to see the Control  class too.
>
> I think the problem might be something you're referencing from 
> there but need to be sure.

Here is some code to reproduce the error in your system.
https://pastebin.com/rgN3ug1e
'this' is not an lvalue.