Hello Stephen,
Interop size of a boolean might be 4 bytes (it's marshalled to Win32 BOOL,
I believe). But the CLR stores booleans as one byte each within GC'd
objects. This is spec'd in ECMA-335, probably Partition II
From a programmer's perspective, it really does not matter how many bytes
it occupies. But I think there may be several reason for adopting 2 bytes
in .NET. First, it makes easier translation to and from other technologies,
for example COM, InterOp, VC. There may be other considerations as well
such as faster execution at the machine code level, in a comparison
operation. Storing it in just one bit may save some space, but it will cost
more time in calculation.
Hope that helps.
Best regards,
Yanhong Huang
Microsoft Online Partner Support
Get Secure! -
www.microsoft.com/security This posting is provided "AS IS" with no warranties, and confers no rights.
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!From: "Stephen" <graybeal@bellatlantic.net>
!Sender: "Stephen" <graybeal@bellatlantic.net>
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!Subject: Re: Boolean type is 2 bytes????
!Date: Sun, 31 Aug 2003 22:59:06 -0700
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!Then why is this:
!Dim a as Boolean
!MsgBox(Len(a))
!Result is 2
!When a is Byte, result is 1
!>-----Original Message-----
!>Stephen,
!>
!>>Why is the Boolean type 2 bytes when all it takes is 1
!>>bit?
!>
!>A Boolean is actually just one byte. There are some
!parts of the
!>VB.NET documentation that says two, but that's incorrect.
!>
!>
!>
!>Mattias
!>
!>--
!>Mattias Sjögren [MVP] mattias @ mvps.org
!>
http://www.msjogren.net/dotnet/ !>Please reply only to the newsgroup.
!>.
!>
!
