The null conditional operator short circuit bad code from executing. The ?. and ?[] operators will return the operand if the operand is not null.
This operator allows code like the following to execute without throwing an exception. In the following example, B isn't evaluated if A evaluates to null and C isn't evaluated if A or B evaluates to null. This example was taken from the Microsoft documentation.
A?.B?.Do(C);
Why don't I just use an example from my code? I can't. I don't code like this. I get what this language feature is doing. What I don't get is why a developer would want to have a statement like that in their code.
This kind of programming needs to have if..then checks to determine what is being used in the subsequent calls. Allowing the null conditional operators to handle this drives me crazy.
How am I supposed to debug this nonsense? Long lines of calls make it incredibly hard to debug. When I have to maintain your code, and I see this, I am going to rewrite it. That is, unless it works, then I would have no business trying to understand what you are doing anyway.
// assume A, B, and C all have values (or not)
var A = GetA();
if (A != null)
{
var B = A.B;
if (B != null)
{
B.Do(C);
}
}
That's how you do it so I can see what is happening in the debugger.