Re: To cast or not to cast?

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You can get data out of SQL CE as Int16 and cast it to UInt16 using
unchecked().
Similarly, cast UInt16 to Int16 to store it.

Another solution would be to declare valuables as signed and let native
code to do interpretation.
That might be problematic if you set values manually somewhere, but it can
be done with unchecked().
Or, you can use equivalent values. For example binary representations of
65535 unsigned and -1 signed for 16 bit values are exactly the same.

Best regards,

Ilya

This posting is provided "AS IS" with no warranties, and confers no rights.

--------------------
> From: "Jeremy" <jezonline@xxxxxxxxxxx>
> References: <umEpDi8OFHA.3880@xxxxxxxxxxxxxxxxxxxx>
<64$0lp9OFHA.1564@xxxxxxxxxxxxxxxxxxxxx>
<#t8wc#BPFHA.1268@xxxxxxxxxxxxxxxxxxxx>
<tz30okGPFHA.920@xxxxxxxxxxxxxxxxxxxxx>
<eTuV9uUPFHA.2568@xxxxxxxxxxxxxxxxxxxx>
<SN73xxVPFHA.920@xxxxxxxxxxxxxxxxxxxxx>
<#Hr63aWPFHA.3336@xxxxxxxxxxxxxxxxxxxx>
<VMZf79WPFHA.920@xxxxxxxxxxxxxxxxxxxxx>
<Oo3kPTgPFHA.580@xxxxxxxxxxxxxxxxxxxx>
<MFm$3ThPFHA.1564@xxxxxxxxxxxxxxxxxxxxx>
<O13JLjhPFHA.2252@xxxxxxxxxxxxxxxxxxxx> <4259bdf6$1@xxxxxxxxxxxxxxxxxx>
<uzZB9okPFHA.3704@xxxxxxxxxxxxxxxxxxxx> <425a0dcf@xxxxxxxxxxxxxxxxxx>
<exZU78uPFHA.1476@xxxxxxxxxxxxxxxxxxxx>
<T4E5kJvPFHA.3136@xxxxxxxxxxxxxxxxxxxxx>
> Subject: Re: To cast or not to cast?
> Date: Wed, 13 Apr 2005 02:00:11 +0100
> Lines: 686
> X-Priority: 3
> X-MSMail-Priority: Normal
> X-Newsreader: Microsoft Outlook Express 6.00.2800.1478
> X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1478
> Message-ID: <#jAmwQ8PFHA.3988@xxxxxxxxxxxxxxxxxxxx>
> Newsgroups: microsoft.public.dotnet.framework.compactframework
> NNTP-Posting-Host: host-84-9-101-26.bulldogdsl.com 84.9.101.26
> Path: TK2MSFTNGXA01.phx.gbl!TK2MSFTNGP08.phx.gbl!tk2msftngp13.phx.gbl
> Xref: TK2MSFTNGXA01.phx.gbl
microsoft.public.dotnet.framework.compactframework:26864
> X-Tomcat-NG: microsoft.public.dotnet.framework.compactframework
>
> the "unsafe" keyword worked great! vs doesn't complain anymore.
>
> I'm trying to solve the UInt16 problem now. I followed your previous
advice
> of using unchecked(). It still says that the value is too small or too
large
> when trying to insert it in the DB using OleDbType.SmallInt (which kind of
> makes sense seeing as the value is 53242).
>
> Any other ideas that could help ?
>
> ""Ilya Tumanov [MS]"" <ilyatum@xxxxxxxxxxxxxxxxxxxx> wrote in message
> news:T4E5kJvPFHA.3136@xxxxxxxxxxxxxxxxxxxxxxxx
> > Unsafe block won't eliminate type check (fortunately). You need to do
> > explicit cast:
> >
> > SecondBIRSample.BiometricData = (IntPtr32)BiometricDataPtr;
> >
> > First error means you need to declare this function with unsafe keyword
> and
> > use /unsafe compiler switch (can be set in project properties).
> >
> > public unsafe void DoUnsafeStuff() {
> > // Can do unsafe stuff here...
> > ..
> > }
> >
> > Best regards,
> >
> > Ilya
> >
> > This posting is provided "AS IS" with no warranties, and confers no
> rights.
> > --------------------
> > > From: "Jeremy" <jezonline@xxxxxxxxxxx>
> > > References: <umEpDi8OFHA.3880@xxxxxxxxxxxxxxxxxxxx>
> > <64$0lp9OFHA.1564@xxxxxxxxxxxxxxxxxxxxx>
> > <#t8wc#BPFHA.1268@xxxxxxxxxxxxxxxxxxxx>
> > <tz30okGPFHA.920@xxxxxxxxxxxxxxxxxxxxx>
> > <eTuV9uUPFHA.2568@xxxxxxxxxxxxxxxxxxxx>
> > <SN73xxVPFHA.920@xxxxxxxxxxxxxxxxxxxxx>
> > <#Hr63aWPFHA.3336@xxxxxxxxxxxxxxxxxxxx>
> > <VMZf79WPFHA.920@xxxxxxxxxxxxxxxxxxxxx>
> > <Oo3kPTgPFHA.580@xxxxxxxxxxxxxxxxxxxx>
> > <MFm$3ThPFHA.1564@xxxxxxxxxxxxxxxxxxxxx>
> > <O13JLjhPFHA.2252@xxxxxxxxxxxxxxxxxxxx> <4259bdf6$1@xxxxxxxxxxxxxxxxxx>
> > <uzZB9okPFHA.3704@xxxxxxxxxxxxxxxxxxxx> <425a0dcf@xxxxxxxxxxxxxxxxxx>
> > > Subject: Re: To cast or not to cast?
> > > Date: Tue, 12 Apr 2005 00:36:01 +0100
> > > Lines: 560
> > > X-Priority: 3
> > > X-MSMail-Priority: Normal
> > > X-Newsreader: Microsoft Outlook Express 6.00.2800.1478
> > > X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1478
> > > Message-ID: <exZU78uPFHA.1476@xxxxxxxxxxxxxxxxxxxx>
> > > Newsgroups: microsoft.public.dotnet.framework.compactframework
> > > NNTP-Posting-Host: host-84-9-101-26.bulldogdsl.com 84.9.101.26
> > > Path:
> >
>
TK2MSFTNGXA01.phx.gbl!TK2MSFTFEED01.phx.gbl!TK2MSFTNGP08.phx.gbl!TK2MSFTNGP0
> > 9.phx.gbl
> > > Xref: TK2MSFTNGXA01.phx.gbl
> > microsoft.public.dotnet.framework.compactframework:26785
> > > X-Tomcat-NG: microsoft.public.dotnet.framework.compactframework
> > >
> > > I tried to follow you fixed() solution, but I get an error saying that
> > > "Pointers can only be used in an unsafe context" and "Cannot
implicitly
> > > convert type void* to System.IntPtr.
> > >
> > > I've got the following down. I think the bit I'm missing is the
> assignment
> > > to IntPtr? And probably the casting as well.. Could you explain though
> > what
> > > the compiler means by the first error? I understand that this is an
> unsafe
> > > block, so why does it complain?
> > >
> > > fixed(void* BiometricDataPtr = (byte[])(bioData[8]))
> > > {
> > > SecondBIRSample.BiometricData = BiometricDataPtr;
> > > }
> > >
> > >
> > > "Ilya Tumanov [MS]" <ilyatum@xxxxxxxxxxxxxxxxxxxx> wrote in message
> > > news:425a0dcf@xxxxxxxxxxxxxxxxxxxxx
> > > > I can see two reasons:
> > > >
> > > >
> > > >
> > > > 1. No need to free the memory after call is done.
> > > >
> > > > 2. No time wasted making temporary copy of something you already
have.
> > > >
> > > >
> > > >
> > > > Best regards,
> > > >
> > > >
> > > >
> > > > Ilya
> > > >
> > > >
> > > > This posting is provided "AS IS" with no warranties, and confers no
> > > rights.
> > > >
> > > > "Alex Feinman [MVP]" <public_news@xxxxxxxxxxxxxxx> wrote in message
> > > > news:uzZB9okPFHA.3704@xxxxxxxxxxxxxxxxxxxxxxx
> > > > > Why would one want to use unsafe blocks is beyond me, when it is
so
> > easy
> > > > > to call LocalAlloc and Marshal.Copy
> > > > >
> > > > > --
> > > > > Alex Feinman
> > > > > ---
> > > > > Visit http://www.opennetcf.org
> > > > > "Ilya Tumanov [MS]" <ilyatum@xxxxxxxxxxxxxxxxxxxx> wrote in
message
> > > > > news:4259bdf6$1@xxxxxxxxxxxxxxxxxxxxx
> > > > >> It won't, but managed array (retrieved from SQL CE) should be
> already
> > > > >> allocated.
> > > > >>
> > > > >>
> > > > >>
> > > > >> Best regards,
> > > > >>
> > > > >>
> > > > >>
> > > > >> Ilya
> > > > >>
> > > > >>
> > > > >>
> > > > >> This posting is provided "AS IS" with no warranties, and confers
no
> > > > >> rights.
> > > > >>
> > > > >>
> > > > >> "<ctacke/>" <ctacke_AT_OpenNETCF_com> wrote in message
> > > > >> news:O13JLjhPFHA.2252@xxxxxxxxxxxxxxxxxxxxxxx
> > > > >>> Though fixed won't allocate any memory for you, so you're still
> > where
> > > > >>> you were before.
> > > > >>>
> > > > >>> -Chris
> > > > >>>
> > > > >>>
> > > > >>> ""Ilya Tumanov [MS]"" <ilyatum@xxxxxxxxxxxxxxxxxxxx> wrote in
> > message
> > > > >>> news:MFm$3ThPFHA.1564@xxxxxxxxxxxxxxxxxxxxxxxx
> > > > >>>> You don't need to do anything to pin memory with fixed(),
fixed()
> > > will
> > > > >>>> do
> > > > >>>> it for you:
> > > > >>>>
> > > > >>>> fixed(void *ArrayPointer = MyManagedArray) {
> > > > >>>> // MyManagedArray is pinned within fixed block and ArrayPointer
> > > points
> > > > >>>> to
> > > > >>>> it.
> > > > >>>> // Assign it to IntPtr (might need some casting) and call
native
> > > > >>>> function
> > > > >>>> within this block.
> > > > >>>> }
> > > > >>>>
> > > > >>>> // MyManagedArray in longer pinned...
> > > > >>>>
> > > > >>>> Best regards,
> > > > >>>>
> > > > >>>> Ilya
> > > > >>>>
> > > > >>>> This posting is provided "AS IS" with no warranties, and
confers
> no
> > > > >>>> rights.
> > > > >>>> --------------------
> > > > >>>>> From: "Jeremy" <jezonline@xxxxxxxxxxx>
> > > > >>>>> References: <umEpDi8OFHA.3880@xxxxxxxxxxxxxxxxxxxx>
> > > > >>>> <64$0lp9OFHA.1564@xxxxxxxxxxxxxxxxxxxxx>
> > > > >>>> <#t8wc#BPFHA.1268@xxxxxxxxxxxxxxxxxxxx>
> > > > >>>> <tz30okGPFHA.920@xxxxxxxxxxxxxxxxxxxxx>
> > > > >>>> <eTuV9uUPFHA.2568@xxxxxxxxxxxxxxxxxxxx>
> > > > >>>> <SN73xxVPFHA.920@xxxxxxxxxxxxxxxxxxxxx>
> > > > >>>> <#Hr63aWPFHA.3336@xxxxxxxxxxxxxxxxxxxx>
> > > > >>>> <VMZf79WPFHA.920@xxxxxxxxxxxxxxxxxxxxx>
> > > > >>>>> Subject: Re: To cast or not to cast?
> > > > >>>>> Date: Sun, 10 Apr 2005 20:37:43 +0100
> > > > >>>>> Lines: 335
> > > > >>>>> X-Priority: 3
> > > > >>>>> X-MSMail-Priority: Normal
> > > > >>>>> X-Newsreader: Microsoft Outlook Express 6.00.2800.1478
> > > > >>>>> X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1478
> > > > >>>>> Message-ID: <Oo3kPTgPFHA.580@xxxxxxxxxxxxxxxxxxxx>
> > > > >>>>> Newsgroups: microsoft.public.dotnet.framework.compactframework
> > > > >>>>> NNTP-Posting-Host: host-84-9-101-26.bulldogdsl.com 84.9.101.26
> > > > >>>>> Path:
> > > TK2MSFTNGXA01.phx.gbl!TK2MSFTNGP08.phx.gbl!TK2MSFTNGP15.phx.gbl
> > > > >>>>> Xref: TK2MSFTNGXA01.phx.gbl
> > > > >>>> microsoft.public.dotnet.framework.compactframework:26681
> > > > >>>>> X-Tomcat-NG:
microsoft.public.dotnet.framework.compactframework
> > > > >>>>>
> > > > >>>>> I did a little bit of research because I'm a newbie regarding
> > > > >>>>> pointers/memory allocation. I found an interesting post by
Brian
> > > > >>>>> Smith:
> > > > >>>>>
> > > > >>>>
> > >
> >
>
http://groups-beta.google.com/group/microsoft.public.dotnet.framework.compac
> > > > >>>>
> > >
> >
>
tframework/browse_frm/thread/d628847ac90ac8a3/b92cb386364174f7?q=unmanaged+a
> > > > >>>> llocate+memory&rnum=10#b92cb386364174f7
> > > > >>>>>
> > > > >>>>> I supose I could use LocalAlloc to allocate memory. The post
> seems
> > > to
> > > > >>>>> be
> > > > >>>>> similar to my problem but I still don't understand how to pin
> > > managed
> > > > >>>> memory
> > > > >>>>> (by using Fixed()?), and have a pointer point to the byte
array
> > > > >>>>> (which is
> > > > >>>>> probably what I would want to do) ?
> > > > >>>>>
> > > > >>>>> your help is really appreciated!
> > > > >>>>>
> > > > >>>>> ""Ilya Tumanov [MS]"" <ilyatum@xxxxxxxxxxxxxxxxxxxx> wrote in
> > > message
> > > > >>>>> news:VMZf79WPFHA.920@xxxxxxxxxxxxxxxxxxxxxxxx
> > > > >>>>> > Creating a new pointer is not enough. You need to allocate
> > memory
> > > > >>>>> > and
> > > > >>>>> > assign value pointing to it to the pointer.
> > > > >>>>> > You might allocate native memory via P/Invoke (which you
would
> > > have
> > > > >>>>> > to
> > > > >>>>> free
> > > > >>>>> > at some point).
> > > > >>>>> > Or, you can obtain a pointer to a managed array you already
> > have.
> > > > >>>>> > Before you pass this pointer to a native code, you have to
pin
> > > > >>>>> > managed
> > > > >>>>> > memory so GC won't move the array.
> > > > >>>>> > You can use GCHandle class for it or you can use unsafe
code.
> > > > >>>>> > I would recommend using Fixed() with unsafe pointer. That
> would
> > > pin
> > > > >>>>> > and
> > > > >>>>> > unpin the array automatically.
> > > > >>>>> > GCHandle has a bug (returns incorrect pointer - there's a
> > > > >>>>> > workaround)
> > > > >>>> and
> > > > >>>>> > it's not automatic.
> > > > >>>>> >
> > > > >>>>> > Best regards,
> > > > >>>>> >
> > > > >>>>> > Ilya
> > > > >>>>> >
> > > > >>>>> > This posting is provided "AS IS" with no warranties, and
> confers
> > > no
> > > > >>>>> rights.
> > > > >>>>> >
> > > > >>>>> > --------------------
> > > > >>>>> > > From: "Jeremy" <jezonline@xxxxxxxxxxx>
> > > > >>>>> > > References: <umEpDi8OFHA.3880@xxxxxxxxxxxxxxxxxxxx>
> > > > >>>>> > <64$0lp9OFHA.1564@xxxxxxxxxxxxxxxxxxxxx>
> > > > >>>>> > <#t8wc#BPFHA.1268@xxxxxxxxxxxxxxxxxxxx>
> > > > >>>>> > <tz30okGPFHA.920@xxxxxxxxxxxxxxxxxxxxx>
> > > > >>>>> > <eTuV9uUPFHA.2568@xxxxxxxxxxxxxxxxxxxx>
> > > > >>>>> > <SN73xxVPFHA.920@xxxxxxxxxxxxxxxxxxxxx>
> > > > >>>>> > > Subject: Re: To cast or not to cast?
> > > > >>>>> > > Date: Sun, 10 Apr 2005 01:46:03 +0100
> > > > >>>>> > > Lines: 240
> > > > >>>>> > > X-Priority: 3
> > > > >>>>> > > X-MSMail-Priority: Normal
> > > > >>>>> > > X-Newsreader: Microsoft Outlook Express 6.00.2800.1478
> > > > >>>>> > > X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1478
> > > > >>>>> > > Message-ID: <#Hr63aWPFHA.3336@xxxxxxxxxxxxxxxxxxxx>
> > > > >>>>> > > Newsgroups:
> microsoft.public.dotnet.framework.compactframework
> > > > >>>>> > > NNTP-Posting-Host: host-84-9-101-26.bulldogdsl.com
> 84.9.101.26
> > > > >>>>> > > Path:
> > > > >>>>> > >
> > TK2MSFTNGXA01.phx.gbl!TK2MSFTNGP08.phx.gbl!TK2MSFTNGP10.phx.gbl
> > > > >>>>> > > Xref: TK2MSFTNGXA01.phx.gbl
> > > > >>>>> > microsoft.public.dotnet.framework.compactframework:26658
> > > > >>>>> > > X-Tomcat-NG:
> > microsoft.public.dotnet.framework.compactframework
> > > > >>>>> > >
> > > > >>>>> > > Okay, so I used the 1040 length, it doesn't seem to
> complain,
> > > > >>>>> > > which is
> > > > >>>>> > good
> > > > >>>>> > > news I guess. To make sure it stores the data correctly
I'm
> > > trying
> > > > >>>>> > > to
> > > > >>>>> > > retrieve it and feed it back to the biometric template
> > matching
> > > > >>>> method.
> > > > >>>>> > >
> > > > >>>>> > > Because it takes IntPtr's for BiometricData and
Signature, I
> > > tried
> > > > >>>>> > creating
> > > > >>>>> > > new pointers and marshal copy the content that I retrieved
> > > earlier
> > > > >>>> into
> > > > >>>>> > > these pointers. I failed. I tried the following:
> > > > >>>>> > >
> > > > >>>>> > > System.IntPtr BiometricDataPtr;//create new pointer
> > > > >>>>> > > BiometricData = (byte[])bioData[8];//BiometricData is an
> array
> > > of
> > > > >>>>> > > type
> > > > >>>>> > byte
> > > > >>>>> > > Marshal.Copy(BiometricData, 0, BiometricDataPtr,
> 1040);//copy
> > > > >>>>> > > content
> > > > >>>> of
> > > > >>>>> > > BiometricData in an IntPtr
> > > > >>>>> > >
> > > > >>>>> > > "Use of unassigned local variable 'BiometricDataPtr'."
> > > > >>>>> > > Obvsiously it's unused, it's meant to point to
something...
> > what
> > > > >>>>> > > am I
> > > > >>>>> > > missing here?
> > > > >>>>> > >
> > > > >>>>> > > ""Ilya Tumanov [MS]"" <ilyatum@xxxxxxxxxxxxxxxxxxxx> wrote
> in
> > > > >>>>> > > message
> > > > >>>>> > > news:SN73xxVPFHA.920@xxxxxxxxxxxxxxxxxxxxxxxx
> > > > >>>>> > > > You should not guess the length, you should know it. It
> > might
> > > be
> > > > >>>> fixed
> > > > >>>>> > or
> > > > >>>>> > > > native code could return it somehow.
> > > > >>>>> > > > Most likely you're correct and FirstBIRSample.Length
> > contains
> > > > >>>>> > > > this
> > > > >>>>> size.
> > > > >>>>> > > > You should check out the documentation for the function
> > you're
> > > > >>>> calling
> > > > >>>>> > to
> > > > >>>>> > > > make sure it's correct.
> > > > >>>>> > > >
> > > > >>>>> > > > If value of a pointer is 0, it's null pointer. It means
> this
> > > > >>>>> > > > pointer
> > > > >>>>> is
> > > > >>>>> > > not
> > > > >>>>> > > > valid and points to nothing.
> > > > >>>>> > > > Since no data is available, you could store it as
DBNull.
> > > > >>>>> > > >
> > > > >>>>> > > > Best regards,
> > > > >>>>> > > >
> > > > >>>>> > > > Ilya
> > > > >>>>> > > >
> > > > >>>>> > > > This posting is provided "AS IS" with no warranties, and
> > > confers
> > > > >>>>> > > > no
> > > > >>>>> > > rights.
> > > > >>>>> > > >
> > > > >>>>> > > > --------------------
> > > > >>>>> > > > > From: "Jeremy" <jezonline@xxxxxxxxxxx>
> > > > >>>>> > > > > References: <umEpDi8OFHA.3880@xxxxxxxxxxxxxxxxxxxx>
> > > > >>>>> > > > <64$0lp9OFHA.1564@xxxxxxxxxxxxxxxxxxxxx>
> > > > >>>>> > > > <#t8wc#BPFHA.1268@xxxxxxxxxxxxxxxxxxxx>
> > > > >>>>> > > > <tz30okGPFHA.920@xxxxxxxxxxxxxxxxxxxxx>
> > > > >>>>> > > > > Subject: Re: To cast or not to cast?
> > > > >>>>> > > > > Date: Sat, 9 Apr 2005 22:32:29 +0100
> > > > >>>>> > > > > Lines: 159
> > > > >>>>> > > > > X-Priority: 3
> > > > >>>>> > > > > X-MSMail-Priority: Normal
> > > > >>>>> > > > > X-Newsreader: Microsoft Outlook Express 6.00.2800.1478
> > > > >>>>> > > > > X-MimeOLE: Produced By Microsoft MimeOLE
V6.00.2800.1478
> > > > >>>>> > > > > Message-ID: <eTuV9uUPFHA.2568@xxxxxxxxxxxxxxxxxxxx>
> > > > >>>>> > > > > Newsgroups:
> > > microsoft.public.dotnet.framework.compactframework
> > > > >>>>> > > > > NNTP-Posting-Host: host-84-9-101-26.bulldogdsl.com
> > > 84.9.101.26
> > > > >>>>> > > > > Path:
> > > > >>>>>
TK2MSFTNGXA01.phx.gbl!TK2MSFTNGP08.phx.gbl!TK2MSFTNGP14.phx.gbl
> > > > >>>>> > > > > Xref: TK2MSFTNGXA01.phx.gbl
> > > > >>>>> > > > microsoft.public.dotnet.framework.compactframework:26653
> > > > >>>>> > > > > X-Tomcat-NG:
> > > > >>>>> > > > > microsoft.public.dotnet.framework.compactframework
> > > > >>>>> > > > >
> > > > >>>>> > > > > Thanks a lot for that! Before going to the UInt16
> > problem, I
> > > > >>>> better
> > > > >>>>> > try
> > > > >>>>> > > to
> > > > >>>>> > > > > solve that IntPtr problem.
> > > > >>>>> > > > >
> > > > >>>>> > > > > Managed to use Marshal.Copy. Not sure how I should
> 'guess'
> > > the
> > > > >>>>> length
> > > > >>>>> > of
> > > > >>>>> > > > the
> > > > >>>>> > > > > Byte array to copy to. When I type
> > > > >>>>> > > > > FirstBIRSample.BiometricData
> > > > >>>>> (which
> > > > >>>>> > > is
> > > > >>>>> > > > > the IntPtr) in the command window, it returns to me:
> > > 2372256 -
> > > > >>>>> > > > > is
> > > > >>>>> this
> > > > >>>>> > > the
> > > > >>>>> > > > > size?
> > > > >>>>> > > > > I 'assumed' the size would be 1040 (which is stored in
> > > > >>>>> > > > > FirstBIRSample.Length).
> > > > >>>>> > > > >
> > > > >>>>> > > > > Second Part: Seems like the FirstBIRSample.Signature
> > (also a
> > > > >>>>> pointer)
> > > > >>>>> > is
> > > > >>>>> > > > 0,
> > > > >>>>> > > > > how should I store this?
> > > > >>>>> > > > >
> > > > >>>>> > > > > Thanks so much!
> > > > >>>>> > > > >
> > > > >>>>> > > > > ""Ilya Tumanov [MS]"" <ilyatum@xxxxxxxxxxxxxxxxxxxx>
> wrote
> > > in
> > > > >>>>> message
> > > > >>>>> > > > > news:tz30okGPFHA.920@xxxxxxxxxxxxxxxxxxxxxxxx
> > > > >>>>> > > > > > While storing UInt16 as Int is OK, it will take more
> > > space.
> > > > >>>>> > > > > > The
> > > > >>>>> > > problem
> > > > >>>>> > > > > > you're having is caused by range check. You might
> > consider
> > > > >>>>> > > > > > using
> > > > >>>>> > > > > > unchecked() to disable it.
> > > > >>>>> > > > > >
> > > > >>>>> > > > > > System.Runtime.InteropServices.Marshal class allows
> you
> > to
> > > > >>>>> > > > > > copy
> > > > >>>>> data
> > > > >>>>> > > > from
> > > > >>>>> > > > > > the pointer to the array. Look into Copy() methods
of
> > that
> > > > >>>> class.
> > > > >>>>> > > > > >
> > > > >>>>> > > > > > Best regards,
> > > > >>>>> > > > > >
> > > > >>>>> > > > > > Ilya
> > > > >>>>> > > > > >
> > > > >>>>> > > > > > This posting is provided "AS IS" with no warranties,
> and
> > > > >>>>> > > > > > confers
> > > > >>>>> no
> > > > >>>>> > > > > rights.
> > > > >>>>> > > > > > --------------------
> > > > >>>>> > > > > > > From: "Jeremy" <jezonline@xxxxxxxxxxx>
> > > > >>>>> > > > > > > References:
<umEpDi8OFHA.3880@xxxxxxxxxxxxxxxxxxxx>
> > > > >>>>> > > > > > <64$0lp9OFHA.1564@xxxxxxxxxxxxxxxxxxxxx>
> > > > >>>>> > > > > > > Subject: Re: To cast or not to cast?
> > > > >>>>> > > > > > > Date: Fri, 8 Apr 2005 10:44:39 +0100
> > > > >>>>> > > > > > > Lines: 91
> > > > >>>>> > > > > > > X-Priority: 3
> > > > >>>>> > > > > > > X-MSMail-Priority: Normal
> > > > >>>>> > > > > > > X-Newsreader: Microsoft Outlook Express
> 6.00.2800.1478
> > > > >>>>> > > > > > > X-MimeOLE: Produced By Microsoft MimeOLE
> > V6.00.2800.1478
> > > > >>>>> > > > > > > Message-ID:
<#t8wc#BPFHA.1268@xxxxxxxxxxxxxxxxxxxx>
> > > > >>>>> > > > > > > Newsgroups:
> > > > >>>>> > > > > > > microsoft.public.dotnet.framework.compactframework
> > > > >>>>> > > > > > > NNTP-Posting-Host: host-84-9-101-26.bulldogdsl.com
> > > > >>>>> > > > > > > 84.9.101.26
> > > > >>>>> > > > > > > Path:
> > > > >>>>> > >
> > TK2MSFTNGXA01.phx.gbl!TK2MSFTNGP08.phx.gbl!TK2MSFTNGP14.phx.gbl
> > > > >>>>> > > > > > > Xref: TK2MSFTNGXA01.phx.gbl
> > > > >>>>> > > > > >
> microsoft.public.dotnet.framework.compactframework:26572
> > > > >>>>> > > > > > > X-Tomcat-NG:
> > > > >>>> microsoft.public.dotnet.framework.compactframework
> > > > >>>>> > > > > > >
> > > > >>>>> > > > > > > Thanks so much for the replies Alex and Ilya!
> > > > >>>>> > > > > > >
> > > > >>>>> > > > > > > I changed the types in sql. It wasn't happy with
> > Uint16
> > > > >>>>> > > > > > > mapped
> > > > >>>>> to
> > > > >>>>> > > > > smallint
> > > > >>>>> > > > > > > (sql says value is either too small or too large),
> so
> > I
> > > > >>>>> > > > > > > just
> > > > >>>>> went
> > > > >>>>> > > for
> > > > >>>>> > > > an
> > > > >>>>> > > > > > > int.
> > > > >>>>> > > > > > >
> > > > >>>>> > > > > > > Not sure how to retrieve the data data an IntPtr
is
> > > > >>>>> > > > > > > pointing
> > > > >>>> to
> > > > >>>>> > > > though.
> > > > >>>>> > > > > > How
> > > > >>>>> > > > > > > can I get that data as a byte array?
> > > > >>>>> > > > > > >
> > > > >>>>> > > > > > > thanks so much again!
> > > > >>>>> > > > > > >
> > > > >>>>> > > > > > > ""Ilya Tumanov [MS]""
<ilyatum@xxxxxxxxxxxxxxxxxxxx>
> > > wrote
> > > > >>>>> > > > > > > in
> > > > >>>>> > > message
> > > > >>>>> > > > > > > news:64$0lp9OFHA.1564@xxxxxxxxxxxxxxxxxxxxxxxx
> > > > >>>>> > > > > > > >
> > > > >>>>> > > > > > >
> > > > >>>>> > > > > >
> > > > >>>>> > > > >
> > > > >>>>> > > >
> > > > >>>>> > >
> > > > >>>>> >
> > > > >>>>>
> > > > >>>>
> > >
> >
>
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/
> > > > >>>>> > > > > > > > frlrfsystemdatasqldbtypeclasstopic.asp
> > > > >>>>> > > > > > > >
> > > > >>>>> > > > > > > > UInt32: Int will do. Signed and Unsigned
integers
> > are
> > > > >>>> actually
> > > > >>>>> > the
> > > > >>>>> > > > > same;
> > > > >>>>> > > > > > > > just cast them to the right type.
> > > > >>>>> > > > > > > > UInt16: SmallInt, see warning above
> > > > >>>>> > > > > > > > Byte: TinyInt
> > > > >>>>> > > > > > > > BioAPI_*: look up underlying type definition and
> use
> > > it.
> > > > >>>> Enums
> > > > >>>>> > are
> > > > >>>>> > > > > Int32
> > > > >>>>> > > > > > > by
> > > > >>>>> > > > > > > > default.
> > > > >>>>> > > > > > > > IntPtr: it's Int32, so store it as Int.
> > > > >>>>> > > > > > > >
> > > > >>>>> > > > > > > > Note, however, it's probably pointless to store
> > > pointers
> > > > >>>>> > > > > > > > in
> > > > >>>>> the
> > > > >>>>> > > data
> > > > >>>>> > > > > > base.
> > > > >>>>> > > > > > > > Pointer itself is not important, most likely you
> > need
> > > to
> > > > >>>> store
> > > > >>>>> > > > > whatever
> > > > >>>>> > > > > > > > it's pointing to.
> > > > >>>>> > > > > > > >
> > > > >>>>> > > > > > > > Best regards,
> > > > >>>>> > > > > > > >
> > > > >>>>> > > > > > > > Ilya
> > > > >>>>> > > > > > > >
> > > > >>>>> > > > > > > > This posting is provided "AS IS" with no
> warranties,
> > > and
> > > > >>>>> confers
> > > > >>>>> > > no
> > > > >>>>> > > > > > > rights.
> > > > >>>>> > > > > > > >
> > > > >>>>> > > > > > > > --------------------
> > > > >>>>> > > > > > > > > From: "Jeremy" <jezonline@xxxxxxxxxxx>
> > > > >>>>> > > > > > > > > Subject: To cast or not to cast?
> > > > >>>>> > > > > > > > > Date: Fri, 8 Apr 2005 00:21:17 +0100
> > > > >>>>> > > > > > > > > Lines: 25
> > > > >>>>> > > > > > > > > X-Priority: 3
> > > > >>>>> > > > > > > > > X-MSMail-Priority: Normal
> > > > >>>>> > > > > > > > > X-Newsreader: Microsoft Outlook Express
> > > 6.00.2800.1478
> > > > >>>>> > > > > > > > > X-MimeOLE: Produced By Microsoft MimeOLE
> > > > >>>>> > > > > > > > > V6.00.2800.1478
> > > > >>>>> > > > > > > > > Message-ID:
> > <umEpDi8OFHA.3880@xxxxxxxxxxxxxxxxxxxx>
> > > > >>>>> > > > > > > > > Newsgroups:
> > > > >>>>> microsoft.public.dotnet.framework.compactframework
> > > > >>>>> > > > > > > > > NNTP-Posting-Host:
> host-84-9-101-26.bulldogdsl.com
> > > > >>>>> 84.9.101.26
> > > > >>>>> > > > > > > > > Path:
> > > > >>>>> > > > >
> > > TK2MSFTNGXA01.phx.gbl!TK2MSFTNGP08.phx.gbl!tk2msftngp13.phx.gbl
> > > > >>>>> > > > > > > > > Xref: TK2MSFTNGXA01.phx.gbl
> > > > >>>>> > > > > > > >
> > > microsoft.public.dotnet.framework.compactframework:26546
> > > > >>>>> > > > > > > > > X-Tomcat-NG:
> > > > >>>>> > microsoft.public.dotnet.framework.compactframework
> > > > >>>>> > > > > > > > >
> > > > >>>>> > > > > > > > > Hi,
> > > > >>>>> > > > > > > > >
> > > > >>>>> > > > > > > > > I'm trying to convert the following types into
> > types
> > > > >>>>> > > > > > > > > that
> > > > >>>> I
> > > > >>>>> > can
> > > > >>>>> > > > > insert
> > > > >>>>> > > > > > > in
> > > > >>>>> > > > > > > > an
> > > > >>>>> > > > > > > > > SQL database (via a webservice). None of these
> > > however
> > > > >>>>> > > > > > > > > are
> > > > >>>>> > > > accepted
> > > > >>>>> > > > > by
> > > > >>>>> > > > > > > Sql
> > > > >>>>> > > > > > > > > (i.e., there is no OleDbType for them). I
could
> > only
> > > > >>>>> > > > > > > > > use
> > > > >>>>> > integer
> > > > >>>>> > > > > type
> > > > >>>>> > > > > > > for
> > > > >>>>> > > > > > > > > UInt32, that's about it. I'm totally unsure
> about
> > > the
> > > > >>>> other
> > > > >>>>> > > types.
> > > > >>>>> > > > > > What
> > > > >>>>> > > > > > > > I've
> > > > >>>>> > > > > > > > > tried doing so far is casting them prior to
> > sending
> > > > >>>>> > > > > > > > > them
> > > > >>>> to
> > > > >>>>> > the
> > > > >>>>> > > > > > > > webservice.
> > > > >>>>> > > > > > > > > When inserting them I get errors though. Would
> > > anyone
> > > > >>>>> > know/could
> > > > >>>>> > > > > point
> > > > >>>>> > > > > > > me
> > > > >>>>> > > > > > > > to
> > > > >>>>> > > > > > > > > types that I could use? Any help would be
really
> > > > >>>>> appreciated,
> > > > >>>>> > > i'm
> > > > >>>>> > > > > > lost!
> > > > >>>>> > > > > > > > >
> > > > >>>>> > > > > > > > > Thanks so much!
> > > > >>>>> > > > > > > > >
> > > > >>>>> > > > > > > > >
> > > > >>>>> > > > > > > > > System.UInt32 Length;
> > > > >>>>> > > > > > > > > System.Byte HeaderVersion;
> > > > >>>>> > > > > > > > > BioAPI_BIR_DATA_TYPE Type;
> > > > >>>>> > > > > > > > > System.UInt16 FormatOwner;
> > > > >>>>> > > > > > > > > System.UInt16 FormatID;
> > > > >>>>> > > > > > > > > System.Byte Quality; /*INT8 BioAPI_QUALITY*/
> > > > >>>>> > > > > > > > > BioAPI_BIR_PURPOSE Purpose;
> > > > >>>>> > > > > > > > > BioAPI_BIR_AUTH_FACTORS FactorsMask;
> > > > >>>>> > > > > > > > > System.IntPtr BiometricData;
> > > > >>>>> > > > > > > > > System.IntPtr Signature;
> > > > >>>>> > > > > > > > >
> > > > >>>>> > > > > > > > >
> > > > >>>>> > > > > > > > >
> > > > >>>>> > > > > > > >
> > > > >>>>> > > > > > >
> > > > >>>>> > > > > > >
> > > > >>>>> > > > > > >
> > > > >>>>> > > > > >
> > > > >>>>> > > > >
> > > > >>>>> > > > >
> > > > >>>>> > > > >
> > > > >>>>> > > >
> > > > >>>>> > >
> > > > >>>>> > >
> > > > >>>>> > >
> > > > >>>>> >
> > > > >>>>>
> > > > >>>>>
> > > > >>>>>
> > > > >>>>
> > > > >>>
> > > > >>>
> > > > >>
> > > > >>
> > > > >
> > > >
> > > >
> > >
> > >
> > >
> >
>
>
>

.

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