c# – Is calling MemoryStream.ToArray() dangerous after disposing? – Education Career Blog

In the below code, is there any chance the GC will clean out the MemoryStream so that ToArray will fail, since it is outside the using statement?

private static byte getBytes()
    MemoryStream ms = null;

    using (ms = new MemoryStream())
        // ...

    return ms.ToArray();


No, there’s no chance of that. It’s safe to do – the MemoryStream keeps a strong reference to the byte array.

I’ll see if I can find any documentation about guarantees…

EDIT: Sort of…

From MemoryStream.Close:

The buffer is still available on a MemoryStream once the stream has been closed.

Admittedly that doesn’t guarantee it for Dispose, but that’s documented to call Stream.Close.

MemoryStream.Dispose(bool) could then be overridden to release the array, but it doesn’t in my experience, and it would be a breaking change at this point.

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