Question

I am use using to guarantee the resource cleanup. This is fine for the simple block of code.
If I have a method which I need to pass the variable inside the using, can I still guarantee resource clean up?

for example,

using ( FileStream fs = -----)
{
      SomeMethod(fs);
}

Answer 1

Yes. using(){} is syntactic sugar, and it will expand your code to this:

FileStream fs = -----;
try {
    SomeMethod(fs);
} finally {
    if (fs != null)
        ((IDisposable)fs).Dispose();
}

finally blocks are guaranteed to execute whether an exception is thrown or not. The only time they wouldn’t be executed is in the case of a severe runtime failure, such as a stack overflow, out of memory exception, or a crash in the runtime itself.