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RandChris
Guest
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 Posted: Thu Apr 01, 2004 10:38 pm Post subject: Passing a two dimensional array from client app to middle ti |
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|
This technique is derived, as best as possible, from the article
http://community.borland.com/article/0,1410,25982,00.htm.
I get an arror from the server portion when attempting execute. The
point at which the error occurs is indicated in upper case notation.
Here is some sample code using the techniques that are in your example.
I am passing an array from a client to a middle layer for further
processing. at the very in, I'll a message 'the server threw an
exception'. If you can help me resolve this I will appreciate it very much.
Please note rfWhereFilter and ParamArray are an array[0..1] of string
{ server code}
procedure TGenRptEngine.AssignWhereFilter(vData: OleVariant);
var
aFilterString : Array of ParamArray ;
pData : PByteArray;
begin
setlength( aFilterString,1);
pData := VarArrayLock( vData ) ;
try
Move( pData^, AFilterString, SizeOf( aFilterString )) ;
finally
VarArrayUnLock( vData ) ;
end;
THE CODE APPEARS TO WORK FINE DOWN TO THIS POINT AS I TESTED IT WITH
MESSAGE BOXES.
ANY ATTEMPT TO ACCESS AN ARRAY ELEMENT WILL GENERATE AN EXCEPTION.
Form1.AssignSelectFilters( aFilterString );
end;
{ END OF SERVER CODE}
{ CLIENT CODE }
procedure TForm1.Button2Click(Sender: TObject);
Var
AWhereFilter : Array of rfWhereFilter ;
VData : Variant;
PData : PByteArray;
begin
cdsFilterString.First ;
{ the data is loaded from a client dataset into an array and then an ole
variant. The client dataset is being temporarily as the final data will
be be read from the registry into an array}
while not cdsFilterString.Eof do begin
{if High( aWhereFilter ) = -1 then
SetLength( aWhereFilter, 1 )
else }
SetLength( aWhereFilter, Max( High(aWhereFilter ) + 1,1) ) ;
aWhereFilter[ High(aWhereFilter),0] := cdsFilterStringCompName.asString ;
aWhereFilter[ High(aWhereFilter),1] := cdsFilterStringCompValue.asString ;
cdsFilterString.Next ;
end;
if High( aWhereFilter ) > -1 then
VData := VarArrayCreate( [0, SizeOf( aWhereFilter ) - 1], varByte );
PData := VarArrayLock( vData ) ;
try
Move(aWhereFilter, PData^, SizeOf(aWhereFilter) ) ;
Finally
VarArrayUnLock( vData ) ;
end;
GenRptEngine.AssignWhereFilter( vData );
{END OF CLIENT CODE}
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Gürcan YÜCEL
Guest
|
| Posted: Fri Apr 02, 2004 8:09 am Post subject: Re: Passing a two dimensional array from client app to middl |
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|
I dont know the reason exactly but,
I was using array streams between client and server. I think it must be in
definite sizes. For this reason use STRING[100] instead STRING in array. I
dont know that array must be in specific size or not.
"RandChris" <RCoyle (AT) pfshouston (DOT) com> wrote
| Quote: | This technique is derived, as best as possible, from the article
http://community.borland.com/article/0,1410,25982,00.htm.
I get an arror from the server portion when attempting execute. The
point at which the error occurs is indicated in upper case notation.
Here is some sample code using the techniques that are in your example.
I am passing an array from a client to a middle layer for further
processing. at the very in, I'll a message 'the server threw an
exception'. If you can help me resolve this I will appreciate it very
much.
Please note rfWhereFilter and ParamArray are an array[0..1] of string
{ server code}
procedure TGenRptEngine.AssignWhereFilter(vData: OleVariant);
var
aFilterString : Array of ParamArray ;
pData : PByteArray;
begin
setlength( aFilterString,1);
pData := VarArrayLock( vData ) ;
try
Move( pData^, AFilterString, SizeOf( aFilterString )) ;
finally
VarArrayUnLock( vData ) ;
end;
THE CODE APPEARS TO WORK FINE DOWN TO THIS POINT AS I TESTED IT WITH
MESSAGE BOXES.
ANY ATTEMPT TO ACCESS AN ARRAY ELEMENT WILL GENERATE AN EXCEPTION.
Form1.AssignSelectFilters( aFilterString );
end;
{ END OF SERVER CODE}
{ CLIENT CODE }
procedure TForm1.Button2Click(Sender: TObject);
Var
AWhereFilter : Array of rfWhereFilter ;
VData : Variant;
PData : PByteArray;
begin
cdsFilterString.First ;
{ the data is loaded from a client dataset into an array and then an ole
variant. The client dataset is being temporarily as the final data will
be be read from the registry into an array}
while not cdsFilterString.Eof do begin
{if High( aWhereFilter ) = -1 then
SetLength( aWhereFilter, 1 )
else }
SetLength( aWhereFilter, Max( High(aWhereFilter ) + 1,1) ) ;
aWhereFilter[ High(aWhereFilter),0] := cdsFilterStringCompName.asString ;
aWhereFilter[ High(aWhereFilter),1] := cdsFilterStringCompValue.asString ;
cdsFilterString.Next ;
end;
if High( aWhereFilter ) > -1 then
VData := VarArrayCreate( [0, SizeOf( aWhereFilter ) - 1], varByte );
PData := VarArrayLock( vData ) ;
try
Move(aWhereFilter, PData^, SizeOf(aWhereFilter) ) ;
Finally
VarArrayUnLock( vData ) ;
end;
GenRptEngine.AssignWhereFilter( vData );
{END OF CLIENT CODE}
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David M
Guest
|
| Posted: Fri Apr 02, 2004 9:18 am Post subject: Re: Passing a two dimensional array from client app to middl |
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On Fri, 2 Apr 2004 11:09:50 +0300, "Gürcan YÜCEL" <gyucel (AT) g-gsoft (DOT) com>
wrote:
| Quote: | I dont know the reason exactly but,
I was using array streams between client and server. I think it must be in
definite sizes. For this reason use STRING[100] instead STRING in array. I
dont know that array must be in specific size or not.
|
For use in multi tier applications pass strings using the Widestring
type. This corresponds to the BSTR IDL type which is a binary string.
Delphi strings are not automation compatible.
For more info see the Help file .
Regards
David M
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RandChris
Guest
|
| Posted: Fri Apr 02, 2004 4:55 pm Post subject: Re: Passing a two dimensional array from client app to middl |
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References: <406c99f9$1 (AT) newsgroups (DOT) borland.com> <406d1f7e (AT) newsgroups (DOT) borland.com> <mqbq60dtl3lj314magc0vm3q907muntr3e (AT) 4ax (DOT) com>
In-Reply-To: <mqbq60dtl3lj314magc0vm3q907muntr3e (AT) 4ax (DOT) com>
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Lines: 32
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I assumed from looking at the code that the array of strings were moved=20
into a variant array prior to being passed. Is this correct from the=20
example provided.
David M wrote:
| Quote: | On Fri, 2 Apr 2004 11:09:50 +0300, "G=FCrcan Y=DCCEL"
om
wrote:
=20
=20
I dont know the reason exactly but,
I was using array streams between client and server. I think it must be=
in
definite sizes. For this reason use STRING[100] instead STRING in array=
=2E I
dont know that array must be in specific size or not.
=20
=20
=20
For use in multi tier applications pass strings using the Widestring
type. This corresponds to the BSTR IDL type which is a binary string.
Delphi strings are not automation compatible.
=20
For more info see the Help file .
=20
Regards
=20
David M
=20
=20
=20
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Tony Blomfield
Guest
|
| Posted: Fri Apr 02, 2004 7:20 pm Post subject: Re: Passing a two dimensional array from client app to middl |
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Here is an working example straigh from a working project. Hope it helps.
Client Side:
procedure TDMCache.GetServerCacheCheckSumArray;
//Transfer the Array of Cache Checksums from the Appserver to the client as
a ByteStream
var
PData: PByteArray;
VData: Variant;
begin
FillChar(FServerMaxCacheIDs, SizeOf(FServerMaxCacheIDs), #0);
Appinfo.RemoteServer.Appserver.AS_GetCacheSumArray(VData);
PData := VarArrayLock(VData);
try
move(PData^, FServerMaxCacheIDs, SizeOf(FServerMaxCacheIDs));
finally
VarArrayUnlock(VData);
end;
end;
Server Side:
procedure TCIDG_RDM.AS_GetCacheSumArray(var CacheSumArray: OleVariant);
var
i : Integer;
TempArray : array[TCacheTableID] of Integer;
PData : PByteArray;
begin
// HelperObject.Logit(nil, 'AS_GetCacheSumArray', kProcedure);
DMCache.GetCacheSumArray(CacheSumArray);
PData:= VarArrayLock(CacheSumArray);
try
move(PData^, TempArray, Sizeof(TempArray));
for i:= 0 to length(FMaxOwnerLevelCacheIDs) - 1 do
begin
TempArray[TCacheTableID(i)]:= TempArray[TCacheTableID(i)] +
FMaxOwnerLevelCacheIDs[TCacheTableID(i)];
end;
move(TempArray, PData^, Sizeof(TempArray));
finally
VarArrayUnlock(CacheSumArray);
end;
end;
"RandChris" <RCoyle (AT) pfshouston (DOT) com> wrote
| Quote: | This technique is derived, as best as possible, from the article
http://community.borland.com/article/0,1410,25982,00.htm.
I get an arror from the server portion when attempting execute. The
point at which the error occurs is indicated in upper case notation.
Here is some sample code using the techniques that are in your example.
I am passing an array from a client to a middle layer for further
processing. at the very in, I'll a message 'the server threw an
exception'. If you can help me resolve this I will appreciate it very
much.
Please note rfWhereFilter and ParamArray are an array[0..1] of string
{ server code}
procedure TGenRptEngine.AssignWhereFilter(vData: OleVariant);
var
aFilterString : Array of ParamArray ;
pData : PByteArray;
begin
setlength( aFilterString,1);
pData := VarArrayLock( vData ) ;
try
Move( pData^, AFilterString, SizeOf( aFilterString )) ;
finally
VarArrayUnLock( vData ) ;
end;
THE CODE APPEARS TO WORK FINE DOWN TO THIS POINT AS I TESTED IT WITH
MESSAGE BOXES.
ANY ATTEMPT TO ACCESS AN ARRAY ELEMENT WILL GENERATE AN EXCEPTION.
Form1.AssignSelectFilters( aFilterString );
end;
{ END OF SERVER CODE}
{ CLIENT CODE }
procedure TForm1.Button2Click(Sender: TObject);
Var
AWhereFilter : Array of rfWhereFilter ;
VData : Variant;
PData : PByteArray;
begin
cdsFilterString.First ;
{ the data is loaded from a client dataset into an array and then an ole
variant. The client dataset is being temporarily as the final data will
be be read from the registry into an array}
while not cdsFilterString.Eof do begin
{if High( aWhereFilter ) = -1 then
SetLength( aWhereFilter, 1 )
else }
SetLength( aWhereFilter, Max( High(aWhereFilter ) + 1,1) ) ;
aWhereFilter[ High(aWhereFilter),0] := cdsFilterStringCompName.asString ;
aWhereFilter[ High(aWhereFilter),1] := cdsFilterStringCompValue.asString ;
cdsFilterString.Next ;
end;
if High( aWhereFilter ) > -1 then
VData := VarArrayCreate( [0, SizeOf( aWhereFilter ) - 1], varByte );
PData := VarArrayLock( vData ) ;
try
Move(aWhereFilter, PData^, SizeOf(aWhereFilter) ) ;
Finally
VarArrayUnLock( vData ) ;
end;
GenRptEngine.AssignWhereFilter( vData );
{END OF CLIENT CODE}
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RandChris
Guest
|
| Posted: Fri Apr 02, 2004 9:53 pm Post subject: Re: Passing a two dimensional array from client app to middl |
|
|
References: <406c99f9$1 (AT) newsgroups (DOT) borland.com> <406dbd5a (AT) newsgroups (DOT) borland.com>
In-Reply-To: <406dbd5a (AT) newsgroups (DOT) borland.com>
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Lines: 141
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Xref: number1.nntp.ash.giganews.com borland.public.delphi.database.multi-tier:45763
Is there a way that you can show this using a 2 dimensional array of
strings being passed from the client to the server. Most importantly I
need to see a 2 dimension array of strings. I can figure how to reverse
the data flow.
Tony Blomfield wrote:
| Quote: | Here is an working example straigh from a working project. Hope it helps.
Client Side:
procedure TDMCache.GetServerCacheCheckSumArray;
//Transfer the Array of Cache Checksums from the Appserver to the client as
a ByteStream
var
PData: PByteArray;
VData: Variant;
begin
FillChar(FServerMaxCacheIDs, SizeOf(FServerMaxCacheIDs), #0);
Appinfo.RemoteServer.Appserver.AS_GetCacheSumArray(VData);
PData := VarArrayLock(VData);
try
move(PData^, FServerMaxCacheIDs, SizeOf(FServerMaxCacheIDs));
finally
VarArrayUnlock(VData);
end;
end;
Server Side:
procedure TCIDG_RDM.AS_GetCacheSumArray(var CacheSumArray: OleVariant);
var
i : Integer;
TempArray : array[TCacheTableID] of Integer;
PData : PByteArray;
begin
// HelperObject.Logit(nil, 'AS_GetCacheSumArray', kProcedure);
DMCache.GetCacheSumArray(CacheSumArray);
PData:= VarArrayLock(CacheSumArray);
try
move(PData^, TempArray, Sizeof(TempArray));
for i:= 0 to length(FMaxOwnerLevelCacheIDs) - 1 do
begin
TempArray[TCacheTableID(i)]:= TempArray[TCacheTableID(i)] +
FMaxOwnerLevelCacheIDs[TCacheTableID(i)];
end;
move(TempArray, PData^, Sizeof(TempArray));
finally
VarArrayUnlock(CacheSumArray);
end;
end;
"RandChris" <RCoyle (AT) pfshouston (DOT) com> wrote in message
news:406c99f9$1 (AT) newsgroups (DOT) borland.com...
This technique is derived, as best as possible, from the article
http://community.borland.com/article/0,1410,25982,00.htm.
I get an arror from the server portion when attempting execute. The
point at which the error occurs is indicated in upper case notation.
Here is some sample code using the techniques that are in your example.
I am passing an array from a client to a middle layer for further
processing. at the very in, I'll a message 'the server threw an
exception'. If you can help me resolve this I will appreciate it very
much.
Please note rfWhereFilter and ParamArray are an array[0..1] of string
{ server code}
procedure TGenRptEngine.AssignWhereFilter(vData: OleVariant);
var
aFilterString : Array of ParamArray ;
pData : PByteArray;
begin
setlength( aFilterString,1);
pData := VarArrayLock( vData ) ;
try
Move( pData^, AFilterString, SizeOf( aFilterString )) ;
finally
VarArrayUnLock( vData ) ;
end;
THE CODE APPEARS TO WORK FINE DOWN TO THIS POINT AS I TESTED IT WITH
MESSAGE BOXES.
ANY ATTEMPT TO ACCESS AN ARRAY ELEMENT WILL GENERATE AN EXCEPTION.
Form1.AssignSelectFilters( aFilterString );
end;
{ END OF SERVER CODE}
{ CLIENT CODE }
procedure TForm1.Button2Click(Sender: TObject);
Var
AWhereFilter : Array of rfWhereFilter ;
VData : Variant;
PData : PByteArray;
begin
cdsFilterString.First ;
{ the data is loaded from a client dataset into an array and then an ole
variant. The client dataset is being temporarily as the final data will
be be read from the registry into an array}
while not cdsFilterString.Eof do begin
{if High( aWhereFilter ) = -1 then
SetLength( aWhereFilter, 1 )
else }
SetLength( aWhereFilter, Max( High(aWhereFilter ) + 1,1) ) ;
aWhereFilter[ High(aWhereFilter),0] := cdsFilterStringCompName.asString ;
aWhereFilter[ High(aWhereFilter),1] := cdsFilterStringCompValue.asString ;
cdsFilterString.Next ;
end;
if High( aWhereFilter ) > -1 then
VData := VarArrayCreate( [0, SizeOf( aWhereFilter ) - 1], varByte );
PData := VarArrayLock( vData ) ;
try
Move(aWhereFilter, PData^, SizeOf(aWhereFilter) ) ;
Finally
VarArrayUnLock( vData ) ;
end;
GenRptEngine.AssignWhereFilter( vData );
{END OF CLIENT CODE}
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RandChris
Guest
|
| Posted: Fri Apr 02, 2004 10:32 pm Post subject: Re: Passing a two dimensional array from client app to middl |
|
|
References: <406c99f9$1 (AT) newsgroups (DOT) borland.com> <406dbd5a (AT) newsgroups (DOT) borland.com>
In-Reply-To: <406dbd5a (AT) newsgroups (DOT) borland.com>
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Xref: number1.nntp.ash.giganews.com borland.public.delphi.database.multi-tier:45764
what is the value of FMaxOwnerLevelCacheIDs and how is it derived?
Tony Blomfield wrote:
| Quote: | Here is an working example straigh from a working project. Hope it helps.
Client Side:
procedure TDMCache.GetServerCacheCheckSumArray;
//Transfer the Array of Cache Checksums from the Appserver to the client as
a ByteStream
var
PData: PByteArray;
VData: Variant;
begin
FillChar(FServerMaxCacheIDs, SizeOf(FServerMaxCacheIDs), #0);
Appinfo.RemoteServer.Appserver.AS_GetCacheSumArray(VData);
PData := VarArrayLock(VData);
try
move(PData^, FServerMaxCacheIDs, SizeOf(FServerMaxCacheIDs));
finally
VarArrayUnlock(VData);
end;
end;
Server Side:
procedure TCIDG_RDM.AS_GetCacheSumArray(var CacheSumArray: OleVariant);
var
i : Integer;
TempArray : array[TCacheTableID] of Integer;
PData : PByteArray;
begin
// HelperObject.Logit(nil, 'AS_GetCacheSumArray', kProcedure);
DMCache.GetCacheSumArray(CacheSumArray);
PData:= VarArrayLock(CacheSumArray);
try
move(PData^, TempArray, Sizeof(TempArray));
for i:= 0 to length(FMaxOwnerLevelCacheIDs) - 1 do
begin
TempArray[TCacheTableID(i)]:= TempArray[TCacheTableID(i)] +
FMaxOwnerLevelCacheIDs[TCacheTableID(i)];
end;
move(TempArray, PData^, Sizeof(TempArray));
finally
VarArrayUnlock(CacheSumArray);
end;
end;
"RandChris" <RCoyle (AT) pfshouston (DOT) com> wrote in message
news:406c99f9$1 (AT) newsgroups (DOT) borland.com...
This technique is derived, as best as possible, from the article
http://community.borland.com/article/0,1410,25982,00.htm.
I get an arror from the server portion when attempting execute. The
point at which the error occurs is indicated in upper case notation.
Here is some sample code using the techniques that are in your example.
I am passing an array from a client to a middle layer for further
processing. at the very in, I'll a message 'the server threw an
exception'. If you can help me resolve this I will appreciate it very
much.
Please note rfWhereFilter and ParamArray are an array[0..1] of string
{ server code}
procedure TGenRptEngine.AssignWhereFilter(vData: OleVariant);
var
aFilterString : Array of ParamArray ;
pData : PByteArray;
begin
setlength( aFilterString,1);
pData := VarArrayLock( vData ) ;
try
Move( pData^, AFilterString, SizeOf( aFilterString )) ;
finally
VarArrayUnLock( vData ) ;
end;
THE CODE APPEARS TO WORK FINE DOWN TO THIS POINT AS I TESTED IT WITH
MESSAGE BOXES.
ANY ATTEMPT TO ACCESS AN ARRAY ELEMENT WILL GENERATE AN EXCEPTION.
Form1.AssignSelectFilters( aFilterString );
end;
{ END OF SERVER CODE}
{ CLIENT CODE }
procedure TForm1.Button2Click(Sender: TObject);
Var
AWhereFilter : Array of rfWhereFilter ;
VData : Variant;
PData : PByteArray;
begin
cdsFilterString.First ;
{ the data is loaded from a client dataset into an array and then an ole
variant. The client dataset is being temporarily as the final data will
be be read from the registry into an array}
while not cdsFilterString.Eof do begin
{if High( aWhereFilter ) = -1 then
SetLength( aWhereFilter, 1 )
else }
SetLength( aWhereFilter, Max( High(aWhereFilter ) + 1,1) ) ;
aWhereFilter[ High(aWhereFilter),0] := cdsFilterStringCompName.asString ;
aWhereFilter[ High(aWhereFilter),1] := cdsFilterStringCompValue.asString ;
cdsFilterString.Next ;
end;
if High( aWhereFilter ) > -1 then
VData := VarArrayCreate( [0, SizeOf( aWhereFilter ) - 1], varByte );
PData := VarArrayLock( vData ) ;
try
Move(aWhereFilter, PData^, SizeOf(aWhereFilter) ) ;
Finally
VarArrayUnLock( vData ) ;
end;
GenRptEngine.AssignWhereFilter( vData );
{END OF CLIENT CODE}
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RandChris
Guest
|
| Posted: Fri Apr 02, 2004 11:33 pm Post subject: Re: Passing a two dimensional array from client app to middl |
|
|
References: <406c99f9$1 (AT) newsgroups (DOT) borland.com> <406dbd5a (AT) newsgroups (DOT) borland.com>
In-Reply-To: <406dbd5a (AT) newsgroups (DOT) borland.com>
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Xref: number1.nntp.ash.giganews.com borland.public.delphi.database.multi-tier:45765
This is interesting. I can make this work, but not with dynamic arrays.
Also, I use the function findcomponent in the middle tier with a
component name that is passed as a string and it will generate a
catastrophic error.
Tony Blomfield wrote:
| Quote: | Here is an working example straigh from a working project. Hope it helps.
Client Side:
procedure TDMCache.GetServerCacheCheckSumArray;
//Transfer the Array of Cache Checksums from the Appserver to the client as
a ByteStream
var
PData: PByteArray;
VData: Variant;
begin
FillChar(FServerMaxCacheIDs, SizeOf(FServerMaxCacheIDs), #0);
Appinfo.RemoteServer.Appserver.AS_GetCacheSumArray(VData);
PData := VarArrayLock(VData);
try
move(PData^, FServerMaxCacheIDs, SizeOf(FServerMaxCacheIDs));
finally
VarArrayUnlock(VData);
end;
end;
Server Side:
procedure TCIDG_RDM.AS_GetCacheSumArray(var CacheSumArray: OleVariant);
var
i : Integer;
TempArray : array[TCacheTableID] of Integer;
PData : PByteArray;
begin
// HelperObject.Logit(nil, 'AS_GetCacheSumArray', kProcedure);
DMCache.GetCacheSumArray(CacheSumArray);
PData:= VarArrayLock(CacheSumArray);
try
move(PData^, TempArray, Sizeof(TempArray));
for i:= 0 to length(FMaxOwnerLevelCacheIDs) - 1 do
begin
TempArray[TCacheTableID(i)]:= TempArray[TCacheTableID(i)] +
FMaxOwnerLevelCacheIDs[TCacheTableID(i)];
end;
move(TempArray, PData^, Sizeof(TempArray));
finally
VarArrayUnlock(CacheSumArray);
end;
end;
"RandChris" <RCoyle (AT) pfshouston (DOT) com> wrote in message
news:406c99f9$1 (AT) newsgroups (DOT) borland.com...
This technique is derived, as best as possible, from the article
http://community.borland.com/article/0,1410,25982,00.htm.
I get an arror from the server portion when attempting execute. The
point at which the error occurs is indicated in upper case notation.
Here is some sample code using the techniques that are in your example.
I am passing an array from a client to a middle layer for further
processing. at the very in, I'll a message 'the server threw an
exception'. If you can help me resolve this I will appreciate it very
much.
Please note rfWhereFilter and ParamArray are an array[0..1] of string
{ server code}
procedure TGenRptEngine.AssignWhereFilter(vData: OleVariant);
var
aFilterString : Array of ParamArray ;
pData : PByteArray;
begin
setlength( aFilterString,1);
pData := VarArrayLock( vData ) ;
try
Move( pData^, AFilterString, SizeOf( aFilterString )) ;
finally
VarArrayUnLock( vData ) ;
end;
THE CODE APPEARS TO WORK FINE DOWN TO THIS POINT AS I TESTED IT WITH
MESSAGE BOXES.
ANY ATTEMPT TO ACCESS AN ARRAY ELEMENT WILL GENERATE AN EXCEPTION.
Form1.AssignSelectFilters( aFilterString );
end;
{ END OF SERVER CODE}
{ CLIENT CODE }
procedure TForm1.Button2Click(Sender: TObject);
Var
AWhereFilter : Array of rfWhereFilter ;
VData : Variant;
PData : PByteArray;
begin
cdsFilterString.First ;
{ the data is loaded from a client dataset into an array and then an ole
variant. The client dataset is being temporarily as the final data will
be be read from the registry into an array}
while not cdsFilterString.Eof do begin
{if High( aWhereFilter ) = -1 then
SetLength( aWhereFilter, 1 )
else }
SetLength( aWhereFilter, Max( High(aWhereFilter ) + 1,1) ) ;
aWhereFilter[ High(aWhereFilter),0] := cdsFilterStringCompName.asString ;
aWhereFilter[ High(aWhereFilter),1] := cdsFilterStringCompValue.asString ;
cdsFilterString.Next ;
end;
if High( aWhereFilter ) > -1 then
VData := VarArrayCreate( [0, SizeOf( aWhereFilter ) - 1], varByte );
PData := VarArrayLock( vData ) ;
try
Move(aWhereFilter, PData^, SizeOf(aWhereFilter) ) ;
Finally
VarArrayUnLock( vData ) ;
end;
GenRptEngine.AssignWhereFilter( vData );
{END OF CLIENT CODE}
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Bill Todd (TeamB)
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| Posted: Sat Apr 03, 2004 12:22 am Post subject: Re: Passing a two dimensional array from client app to middl |
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On Fri, 02 Apr 2004 15:53:21 -0600, RandChris <RCoyle (AT) pfshouston (DOT) com>
wrote:
| Quote: | Is there a way that you can show this using a 2 dimensional array of
strings being passed from the client to the server. Most importantly I
need to see a 2 dimension array of strings. I can figure how to reverse
the data flow.
|
Take a look in the Language Reference at the explanation of how Delphi
strings are stored and you will see why this will not work. It works
with static arrays of fixed size values because the data are stored in
adjacent bytes in memory. Strings are not stored that way. Delphi
strings are basically pointers to dynamically allocated blocks of
memory. There is no continuous stream of bytes that can be copied to a
byte array.
--
Bill (TeamB)
(TeamB cannot respond to questions received via email)
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Rafel Coyle
Guest
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| Posted: Sat Apr 03, 2004 1:43 am Post subject: Re: Passing a two dimensional array from client app to middl |
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References: <406c99f9$1 (AT) newsgroups (DOT) borland.com> <406dbd5a (AT) newsgroups (DOT) borland.com> <406de0ce$1 (AT) newsgroups (DOT) borland.com> <u80s605nqj0i8j1nnan79k7hb0laioiel9 (AT) 4ax (DOT) com>
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Transfer-Encoding: 7bit
NNTP-Posting-Host: 24.233.62.5
X-Trace: newsgroups.borland.com 1080956626 24.233.62.5 (2 Apr 2004 17:43:46 -0800)
Lines: 31
Path: number1.nntp.ash.giganews.com!internal1.nntp.ash.giganews.com!border2.nntp.ash.giganews.com!nntp.giganews.com!feed2.newsreader.com!newsreader.com!newshosting.com!nx02.iad01.newshosting.com!203.109.252.33.MISMATCH!newsfeeds.ihug.co.nz!ihug.co.nz!newsgroups.borland.com!not-for-mail
Xref: number1.nntp.ash.giganews.com borland.public.delphi.database.multi-tier:45767
Thank you.
Now I will have to find a way to make findcomponent work in the middle
tier app. There I have a form with a tabsheet that is the parent of a
frame. Findcomponent works if I run the server app as a program, but if
I call it as an automation server an error is generated in the middle
tier app.
Bill Todd (TeamB) wrote:
| Quote: | On Fri, 02 Apr 2004 15:53:21 -0600, RandChris
wrote:
Is there a way that you can show this using a 2 dimensional array of
strings being passed from the client to the server. Most importantly I
need to see a 2 dimension array of strings. I can figure how to reverse
the data flow.
Take a look in the Language Reference at the explanation of how Delphi
strings are stored and you will see why this will not work. It works
with static arrays of fixed size values because the data are stored in
adjacent bytes in memory. Strings are not stored that way. Delphi
strings are basically pointers to dynamically allocated blocks of
memory. There is no continuous stream of bytes that can be copied to a
byte array.
--
Bill (TeamB)
(TeamB cannot respond to questions received via email)
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Bill Todd (TeamB)
Guest
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| Posted: Sat Apr 03, 2004 2:45 am Post subject: Re: Passing a two dimensional array from client app to middl |
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By the way, as someone else pointed out in this thread, it should work
if you use the old style Pascal short strings. For example,
Foo: array[0..9] of String[40];
--
Bill (TeamB)
(TeamB cannot respond to questions received via email)
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Rafel Coyle
Guest
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| Posted: Sat Apr 03, 2004 6:44 am Post subject: Re: Passing a two dimensional array from client app to middl |
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References: <406c99f9$1 (AT) newsgroups (DOT) borland.com> <406dbd5a (AT) newsgroups (DOT) borland.com> <406de0ce$1 (AT) newsgroups (DOT) borland.com> <u80s605nqj0i8j1nnan79k7hb0laioiel9 (AT) 4ax (DOT) com> <406E16D5.1080709 (AT) nospamplspfshouston (DOT) com> <e79s601ppv7n3vt4eqn3mdei4ppv18l47i (AT) 4ax (DOT) com>
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Transfer-Encoding: 7bit
NNTP-Posting-Host: 24.233.62.5
X-Trace: newsgroups.borland.com 1080974681 24.233.62.5 (2 Apr 2004 22:44:41 -0800)
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Xref: number1.nntp.ash.giganews.com borland.public.delphi.database.multi-tier:45770
Thanks Bill. Actually, I used Array[0..20] of array[0..1] of string[30]
Bill Todd (TeamB) wrote:
| Quote: | By the way, as someone else pointed out in this thread, it should work
if you use the old style Pascal short strings. For example,
Foo: array[0..9] of String[40];
--
Bill (TeamB)
(TeamB cannot respond to questions received via email)
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