Throw an exception if an object is null

Question

I've recently discovered that this:

if (Foo() != null)
    { mymethod(); }

can be rewritten as:

Foo?.mymethod()

Can the following be rewritten in a similar fashion?

if (Foo == null)
    { throw new Exception() }

Answer 1

I don't know why you would..

public Exception GetException(object instance)
{
    return (instance == null) ? new ArgumentNullException() : new ArgumentException();
}

public void Main()
{
    object something = null;
    throw GetException(something);
}