What VB variable is compatible with a DWORD?

[RyanCross]

What VB variable is compatible with a DWORD?

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Thank you,
Ryan M. Cross
Webmaster FlexiFish Inc. UK
Likuid Creations Inc.

[Paul Squires]

As far as I know I think a LONG is about as close as
you will get. The LONG is signed (+/-) in VB whereas the
DWORD is unsigned (+) in PB.



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Paul Squires
[email protected]

[Wayne Diamond]

VB numeric data-types:
INTEGER (2 bytes): -32,768 to 32,767
LONG (4 bytes): -2,147,483,648 to 2,147,483,647
SINGLE-precision-floating-point (4 bytes): -3.402823E38 to -1.401298E-45 for negative values, 1.401298E-45 to 3.402823E38 for positive values
DOUBLE-precision-floating-point (8 bytes): -1.7976931344862315D308 to -4.94066D-324 for negative values, 4.94066D-324 to 1.797693134862315D308 for positive values
CURRENCY-scaled-integer (8 bytes): -922337203685477.5808 to 922337203685477.5807

but if youre like me and cant add up beyond 10, just stick to integers <grin>


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[Cecil Williams]

Ryan,

I would be very careful in trying to stuff a DWORD into a
LONG. A Double Word is 32 bits (4 bytes), unsigned
0 to 4,294,967,295 while a LONG is 2,147,483,647 on the
positive side.

For the most part you may be able to get by, BUT!!!!!!!!!

Cecil

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[Paul Dwyer]

Surly you could pass a long!

But if you know that your app is being called by VB then use a check. If the number is positive then it will fit, and if negative then convert (assumably with the two's compliment rule)
even if a negative is passed your dword will see it as a positive, but the area you need to be carefull of is passing a number too large for a long from a dword and having VB think it is negative. that could cause problems depending on what you are doing.

Better still

Test it! in the environment that it has to work in and most importantly Comment and document so people know what you've done.



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Paul Dwyer
Network Engineer
Aussie in Tokyo
(Paul282 at VB-World)

[John Kovacich]

Ryan,

I am going to take a completely different stab at answering your question.
Since you didn't say what prompted your question, I will consider what
VB can pass to PB in the form of a DWORD.

If you pass an ARRAY from VB to PB by reference as:

call PBDLLroutine(MyArray())

Then PB would read the array as:

SUB PBDLLroutine ALIAS "PBDLLroutine" (MyArrayHeader as DWORD) EXPORT
DIM MyArrayDim as LONG
DIM MyArrayAddr as DWORD

MyArrayDim = vbArrayUBound(MyArrayHeader,1)
MyArrayAddr = vbArrayFirstElem(MyArrayHeader)
DIM MyArray(MyArrayDim) AT MyArrayAddr

So VB itself uses DWORD values, but it doesn't give us an equivilant
data type to use.



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[Michael Mattias]

You can always.....

DWORDval = BITS???(LongVal)

Of course, this only works on the PB side.

MCM