即使在 C# 中调用 GC.Collect() 之后，对于 int 变量，GC.GetGeneration() 始终返回 0

Question

Below is code snippet in which I am getting generation of variable int j before and after calling garbage collector.

int j = 30;
WriteLine(GC.GetGeneration(j) );
GC.Collect();
WriteLine(GC.GetGeneration(j));

The output should be

0
1

as int j is surviving garbage collection But I am getting

0
0

I don't understand why this is happening because int is also an object in C#. PS: I have tried running project in debug as well as in release mode.

Answer 1

As mentioned in the comments. an int is a value type and is not tracked by the garbage collector. Since GetGeneration takes an object , the int will be boxed . Ie a new object will be created. That new object will always be allocated in gen 0. The next time you call GetGeneration the same thing will occur.

So your results are as expected.