Are the following code snippets equivalent?
class a
{}
class b:a
{}
开发者_JAVA百科
b foo=new b();
//here it comes
foo is a
//...is the same as...
typeof(a).isinstanceoftype(foo)
Or maybe one of the other Type Methods map closer to the is operator. e.g. "IsAssignableFrom" or "IsSubclassOf"
It isn't, because is
is tolerant to null reference at the left-hand side.
It's not the same as is
is translated into the isinst opcode whereas IsInstanceOf
is a normal virtual call on Type
.
No it's not. In fact, if you peek into IsInstanceOfType
you will see that the very first code line actually performs a comparison using is
, which would effectively lead to a StackOverflowException
if that was the case.
The is
operator leads to an isinst
operation in the IL code.
精彩评论