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