C / C++ / MFC

about variant fonctions?? [modified]

12-Mar-08 23:17

OnInitialUpdate() ?

nave

[OpenedFileFinder]

savitri12-Mar-08 23:09

12-Mar-08 23:09

hello everyone,
good afternoon to all, i am creating OCX files so i want to use variant parameter.please tell me how it should declared and where should be declared. i declared like this:
in ACR120RWctl.h
CString strVerifyKeyA;
CString VerifyKeyA(int SectorNo, VARIANT strVerifyKeyA="ss");
is it right way to declaration or not.
in ACR120RWctl.cpp i am using these functions.
if i am setting the field and scode as follows then it is giving error.
strVerifyKeyA.vt=VT_ERROR;
strVerifyKeyA.scode=DISP_E_PARAMNOTFONUD;
it is giving error.and if i want to assign sring value to that variable then also it is giving error.

please help me.i am in tension.
HELP ME.

THANKU IN ADVANCED,
savitri Confused | :confused:

modified on Thursday, March 13, 2008 5:21 AM

Maxwell Chen12-Mar-08 23:26

Maxwell Chen

12-Mar-08 23:26

savitri wrote:
CString VerifyKeyA(int SectorNo, VARIANT strVerifyKeyA);

Syntax is OK for this prototype of function.

This prototype means:
Function VerifyKeyA takes two parameters:
the first one is of type int named SectorNo,
the second one is of type VARIANT.
But according to the name strBerifyKeyA, it is treated as a string.

This function returns an object of type CString, which is of course, a string.

But honestly, a verification procedure should return seccess / failure, which would be type BOOL or bool;
Or some kind of return value (Status WORD) to represent the verification result.

Maxwell Chen

savitri12-Mar-08 23:35

12-Mar-08 23:35

thanku i am also retuning string value only.so i take it as string.but how shall i assign the value to this variable. if i will assign CString verifykeyA(int sectorno,VARIANT strVerifyKeyA="");then it is giving error. please help me..

thanku,
savitri Cry | :((

Maxwell Chen12-Mar-08 23:49

Maxwell Chen

12-Mar-08 23:49

Before you feed that VARIANT type variable as the argument to the function, you need to configure that VARIANT variable.

And while review your modified post, I guess that you are using the prototype in function implementation as an expression?! WTF | :WTF:

What you have to do is ...

CString s;
VARIANT v;
BSTR bstr = s.AllocSysString();
v.vt = VT_BSTR;
v.bstrVal = bstr;
VerifyKeyA(SecNo, v);
::SysFreeString(bstr);

Maxwell Chen

savitri13-Mar-08 0:49

13-Mar-08 0:49

hi..
i write like this in .h or header file
CString strVerifyKeyA;
VARIANT strVerifyKeyAwith;
BSTR bstr1=strVerifyKeyA.AllocSysString();
strVerifyKeyAwith.vt=VT_BSTR;
strVerifyKeyAwith.bstrVal=bstr1;

CString strVerifyKeyB;
VARIANT strVerifyKeyBwith;
BSTR bstr2=strVerifyKeyB.AllocSysString();
strVerifyKeyBwith.vt=VT_BSTR;
strVerifyKeyBwith.bstrVal=bstr2;

CString strPort;
VARIANT strPort1;
BSTR port=strPort.AllocSysString();
strPort1.vt=VT_BSTR;
strPort1.bstrVal=port;

CString VerifyKeyA(int SectorNo, strVerifyKeyAwith);
CString VerifyKeyB( int SectorNo, strVerifyKeyBwith);
int InitReader(strPort1="");
long DisconnectReader(int ReaderHandle);
in .cpp file i added the code of initreader(strPort1="USB1")
{
}

but i am getting error like this as follows:
error C2327: 'CACR120RWCtrl::strVerifyKeyA' : member from enclosing class is not a type name, static, or enumerator
error C2065: 'strVerifyKeyA' : undeclared identifier
C2228: left of '.AllocSysString' must have class/struct/union type
error C2258: illegal pure syntax, must be '= 0'
error C2252: 'bstr1' : pure specifier can only be specified for functions
error C2143: syntax error : missing ';' before '.'
C2501: 'strVerifyKeyAwith' : missing storage-class or type specifiers
error C2059: syntax error : '.'
error C2238: unexpected token(s) preceding ';'
studio\myprojects\acr120rw\acr120rwctl.h error C2143: syntax error : missing ';' before '.'
c:\program files\microsoft visual studio\myprojects\acr120rw\acr120rwctl.h(21) : error C2501: 'strVerifyKeyAwith' : missing storage-class or type specifiers
please help me.
thanku.
savitri: Confused | :confused:

savitri13-Mar-08 1:22

13-Mar-08 1:22

hi max,
i am used how u told me.but when i called that function in another function then it is showing that VerifyKeyA(3); does not take 1 parameter.if i am giving like this :VerifyKeyA(3,"");then it is giving error like this:cannot convert parameter 2 from 'char [1]' to 'struct tagVARIANT'.Please Help me. i am in confusion.or else tell me some reference book that i will read from those books. please do it. REPLY ME.

THANKU,
savitri Confused | :confused:

Rajesh R Subramanian13-Mar-08 1:31

13-Mar-08 1:31

Buy a book which has ALL of the following terms (in any order) in the title:

1. C++/C
2. Complete idiot
3. Guide

After you finish reading it, please give it to li zhuyuiyan or whatever his name is.

Nobody can give you wiser advice than yourself. - Cicero
.·´¯`·->Rajesh<-·´¯`·.
Codeproject.com: Visual C++ MVP

How to install VisualStudio .NET 2003 in VISTA?

Rajkumar R13-Mar-08 3:34

Rajkumar R

13-Mar-08 3:34

Rajesh R Subramanian wrote:
After you finish reading it, please give it to li zhuyuiyan or whatever his name is.

you cannot find him anymore in this name he is now "gentleguy".

rowdy_vc++12-Mar-08 22:55

rowdy_vc++

12-Mar-08 22:55

hi to All
i dont know ..how to install visual studio 2003 in Windows Vista.When i execute the .EXE file showing some missing components ..so please tell me how to install in VIsta...

*****THANKS N ADVANCE****
Mathen.K
(I WILL TRY MY LEVEL BEST )

Re: How to install VisualStudio .NET 2003 in VISTA? {Mod}

Programm3r12-Mar-08 23:13

Re: How to install VisualStudio .NET 2003 in VISTA?

12-Mar-08 23:13

Install VS 2K3 in Vista[^]

More specific...[^]

Regards,

The only programmers that are better that C programmers are those who code in 1's and 0's Green Alien | [Alien]

Programm3r
My Blog: ^_^

Hamid_RT21-Mar-08 5:03

Hamid_RT

21-Mar-08 5:03

Why you didnt use of VS2005 or VS2008?

DLL passing EXE parameters

Programm3r12-Mar-08 22:53

12-Mar-08 22:53

Hi all,

First of all, excuse me if this is a stupid question but, I would like to know whether there is any way that a dll can pass arguments to a exe.

Mant thanks in advance
Regards,

The only programmers that are better that C programmers are those who code in 1's and 0's Green Alien | [Alien]

Programm3r
My Blog: ^_^

Rajesh R Subramanian12-Mar-08 22:56

12-Mar-08 22:56

What exactly do you mean by passing an argument?

Nobody can give you wiser advice than yourself. - Cicero
.·´¯`·->Rajesh<-·´¯`·.
Codeproject.com: Visual C++ MVP

Programm3r12-Mar-08 23:04

12-Mar-08 23:04

Well, I'm not sure if this qualifies, but something like, starting an application from a shell function and in the file name path. one enters some arguments. i.e. C:\myApp.exe -testing

Then the exe can pick up the 'argument' passed by the dll

Makes sense?

Thanks for the reply
Regards,

The only programmers that are better that C programmers are those who code in 1's and 0's Green Alien | [Alien]

Programm3r
My Blog: ^_^

Rajesh R Subramanian12-Mar-08 23:11

Re: DLL passing EXE parameters {mod}

12-Mar-08 23:11

You're still not very clear. I am assuming that you're spawning an executable from within a DLL by using something like ShellExecute(). If yes, the executable can pick up the 'argument' being passed on to it. Why not write a small program and test it out? Smile | :)

Nobody can give you wiser advice than yourself. - Cicero
.·´¯`·->Rajesh<-·´¯`·.
Codeproject.com: Visual C++ MVP

Programm3r12-Mar-08 23:15

Re: DLL passing EXE parameters {mod}

12-Mar-08 23:15

Rajesh R Subramanian wrote:
am assuming that you're spawning an executable from within a DLL by using something like ShellExecute().

Exactly

Rajesh R Subramanian wrote:
the executable can pick up the 'argument' being passed on to it

Any functions that may help? int main(int argc, char* argv[])
Never mind Smile | :)

Rajesh R Subramanian wrote:
Why not write a small program and test it out?

For sure... Smile | :)

Many thanks
Regards,

The only programmers that are better that C programmers are those who code in 1's and 0's Green Alien | [Alien]

Programm3r
My Blog: ^_^

Rajesh R Subramanian12-Mar-08 23:25

12-Mar-08 23:25

Programm3r wrote:
Any functions that may help?

m_lpCmdLine holds the command line passed to an MFC app. Smile | :)

Nobody can give you wiser advice than yourself. - Cicero
.·´¯`·->Rajesh<-·´¯`·.
Codeproject.com: Visual C++ MVP

Naveen12-Mar-08 23:00

12-Mar-08 23:00

Programm3r wrote:
dll can pass arguments to a exe.

I hope the "exe" you meant is the exe that loaded the dll. if so can use the following methods.

1. Call back functions
2. Sending/posting message
3. Shared memory and Events...

nave

[OpenedFileFinder]

Programm3r12-Mar-08 23:07

12-Mar-08 23:07

Naveen wrote:
I hope the "exe" you meant is the exe that loaded the dll

.... mmmmm ..... no. It's a dll starting the exe (application), and I want to 'pass' the application a value.

I can put the value into a temp file from the dll, and the application can read the value, but I just though, is there a better way?

Thanks for the response
Regards,

The only programmers that are better that C programmers are those who code in 1's and 0's Green Alien | [Alien]

Programm3r
My Blog: ^_^

Naveen12-Mar-08 23:14

12-Mar-08 23:14

Programm3r wrote:
is there a better way?

is there any pblm in passing those data as CommandLine to the exe?

nave

[OpenedFileFinder]

Programm3r12-Mar-08 23:19

12-Mar-08 23:19

Naveen wrote:
is there any pblm in passing those data as CommandLine to the exe?

No ... I think it will do the job.

Thanks for the help
Regards,

The only programmers that are better that C programmers are those who code in 1's and 0's Green Alien | [Alien]

Programm3r
My Blog: ^_^

Naveen12-Mar-08 23:27

12-Mar-08 23:27

Then what is the problem?
if ur using the ShellExecute() function..set the command line arguments to the "lpParameters" of the ShellExecute() function.

And from the EXE you get this command line using the GetCommandLine() funtion.

nave

[OpenedFileFinder]

Programm3r12-Mar-08 23:37