can we take a data member by static_cast and assign to another ??

Question

we have an "objectA" from classA that has a data member ptr and other members:

void *ptr;

we have ClassB that has a data member ctxptr.

void * ctxptr;

ClassB(classA & objectA) :
ctxptr(static_cast <void*>(objectA) )
{
}

here use from member initialize list.

I think it could as follow:

ctxptr = objectA.ptr;

but I can't understand another synatax.

Answer 1

static_cast <type-id> ( expression )

Converts an expression to the type of type-id, based only on the types that are present in the expression.

The static_cast operator can be used for operations such as converting a pointer to a base class to a pointer to a derived class. Such conversions are not always safe.

static_cast conversions are not as safe as dynamic_cast conversions, because static_cast does no run-time type check, while dynamic_cast does.

A dynamic_cast to an ambiguous pointer will fail, while a static_cast returns as if nothing were wrong; this can be dangerous. Although dynamic_cast conversions are safer, dynamic_cast only works on pointers or references, and the run-time type check is an overhead.

https://code.sololearn.com/cuh4DJwwg6hm

more information:
https://docs.microsoft.com/en-us/cpp/cpp/static-cast-operator?view=vs-2019