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Re: Build Configurations

David Crow19-Apr-04 5:13

19-Apr-04 5:13

Check out the _T() macro:

TRACE(_T("Hello build with UNICODE support"));

"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)

Re: Build Configurations

Demian Panello19-Apr-04 5:25

19-Apr-04 5:25

Hi.

I'm using the marco _T() indeed.

The macro _T() wrapped L.

Demian.

Re: Build Configurations

David Crow19-Apr-04 5:29

19-Apr-04 5:29

Demian Panello wrote:
The macro _T() wrapped L.

Of course. And in the case where _UNICODE is not defined, _T() resolves to nothing. This will eliminate the need for all of the #ifdef directives.

"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)

Re: Build Configurations

Demian Panello19-Apr-04 5:41

19-Apr-04 5:41

Hi David.

You are right!
This is the solution, at least with TRACE() an others functions.

Thank you very much.

Demian.

icem4n19-Apr-04 4:37

19-Apr-04 4:37

corelibc.lib(pegwmain.obj) : error LNK2019: unresolved external symbol _WinMain referenced in function _WinMainCRTStartup
X86Dbg/image.exe : fatal error LNK1120: 1 unresolved externals
Error executing link.exe.

i have this kind of error message but i dont have any clue ... i think something wrong with the emulator ? im using eVC 3.0 and i try eVC 4.0 sp3 but same result....

Re: error message

Navin19-Apr-04 5:42

19-Apr-04 5:42

Just a guess - but it sounds like the project settings don't match reality - for instance, you have your project set up to build a Windows application, but you have coded a console application.

Sometimes I feel like I'm a USB printer in a parallel universe.

Extending the WAB Context Menu Actions Source Code

Pyramid119-Apr-04 4:36

19-Apr-04 4:36

Someone know where I can find same examples look at Extending the WAB (windows address book) Context Menu Actions

Tanks in advice.

Matteo

typeid operator

kfaday19-Apr-04 4:28

19-Apr-04 4:28

Hello

I've got a vehicle class (cVehicle), and two 'heirs', car (cCar)and van (cVan). I store cars and vans in a list. The cvehicle class has a vehicle_type atribute (a char that is 'c' when it's a car and 'v' if it's a van). I want to take it out.

in the following code, i get a vehicle from a list. I don;t know if it's a car or it's a van. I use the vehicle_type atribute to see if it's a car, and if it is, i must return it.

<br />
		cvehicle *vtemp=(list->Getvehicle());<br />
		if (vtemp->get_vehicle_type()=='c')<br />
  	 	 				return vtemp;<br />
<br />

i've heard of a more elegant way to solve it, that is with the typeid operator. Do you know how to use it?

thanks!

Re: typeid operator

toxcct19-Apr-04 4:33

19-Apr-04 4:33

do you know MSDN ?

i cite :

typeid Operator
C++ Specific —>

<code>typeid( type-id )
typeid( expression )</code>
 
The <code>typeid </code>operator allows the type of an object to be determined at run-time.

The result of a <code>typeid </code>expression is a <code>const type_info&</code>. The value is a reference to a <code>type_info </code>object that represents either the type-id or
the type of the expression, depending on which form of <code>typeid </code>is used.
See type_info Class for more information.

END C++ Specific

here you are

TOXCCT >>> GEII power

Re: typeid operator

kfaday19-Apr-04 4:38

19-Apr-04 4:38

sorry, i'm new to c++ and i don't have msdn cds.
would you mind giving me an example of typeid usage, if it's not too much trouble?

Re: typeid operator

jmkhael19-Apr-04 5:09

19-Apr-04 5:09

string clss;
if (typeid(obj)==typeid(int)) clss = "I";
else if (typeid(obj)==typeid(unsigned int)) clss = "i";
else if (typeid(obj)==typeid(float)) clss = "F";
else if (typeid(obj)==typeid(double)) clss = "D";
else if (typeid(obj)==typeid(short)) clss = "B";
else if (typeid(obj)==typeid(unsigned short)) clss = "b";
else if (typeid(obj)==typeid(long)) clss = "I";
else if (typeid(obj)==typeid(unsigned long)) clss = "i";

got the idea? Smile | :)

Smile | :)

Papa

while (TRUE)
Papa.WillLove ( Bebe ) ;

Re: typeid operator

kfaday19-Apr-04 5:46

19-Apr-04 5:46

i tried this but it doesn't work

cvehicle *vtemp=(list->Getvehicle());
if (typeid(vtemp)==typeid(ccar)))
return vtemp;

Re: typeid operator

jmkhael19-Apr-04 5:58

19-Apr-04 5:58

just tried this and it works

CString temp;
CString temp1;
const type_info& t = typeid(temp);
AfxMessageBox (t.name ()); // It gave class CString

if(typeid(temp1) == typeid(CString))
AfxMessageBox ("Matched"); // It said matched

Check this too:

class Base { ... };

class Derived : public Base { ... };

void f()
{
Derived* pd = new Derived;
Base* pb = pd;
...
const type_info& t = typeid(pb); // t holds pointer type_info
const type_info& t1 = typeid(*pb); // t1 holds Derived info
...
}
(This is your prob, you should dereference the pointer)

What does yours do?

Papa

while (TRUE)
Papa.WillLove ( Bebe ) ;

Re: typeid operator

kfaday19-Apr-04 6:53

19-Apr-04 6:53

t and t1 are always diferent!

from the debugger:
t: + _m_d_name 0x00433890 ".PAVcvehicle@@"
t1: + _m_d_name 0x00433850 ".?AVccar@@"

Re: typeid operator

jmkhael19-Apr-04 6:56

19-Apr-04 6:56

yes so check it against t1

dereference first the pointer you receive and then compare it to typeid(ccar)

Papa

while (TRUE)
Papa.WillLove ( Bebe ) ;

Re: typeid operator

kfaday19-Apr-04 7:01

19-Apr-04 7:01

Papa wrote:
dereference first the pointer you receive and then compare it to typeid(ccar)

what do you mean by this?
sorry, english isn't my first language

Re: typeid operator

jmkhael19-Apr-04 7:03

19-Apr-04 7:03

cvehicle *vtemp=(list->Getvehicle());
if (typeid(*vtemp)==typeid(ccar)))
return vtemp;

Papa

while (TRUE)
Papa.WillLove ( Bebe ) ;

Re: typeid operator

kfaday19-Apr-04 7:07

19-Apr-04 7:07

it gives me an error: (runtime error, it builds alright)
unhandled exception

Re: typeid operator

jmkhael19-Apr-04 7:14

19-Apr-04 7:14

"If the expression is dereferencing a pointer, and that pointer’s value is zero, typeid throws a bad_typeid exception. If the pointer does not point to a valid object, a __non_rtti_object exception is thrown."

Do you have a NULL pointer?

Papa

while (TRUE)
Papa.WillLove ( Bebe ) ;

Re: typeid operator

kfaday19-Apr-04 7:48

19-Apr-04 7:48

no, *vtemp isn't null

it gives me this warning

warning C4541: 'typeid' used on polymorphic type 'class ccar' with /GR-; unpredictable behavior may result

Re: typeid operator

antlers19-Apr-04 12:04

19-Apr-04 12:04

typeid depends on RTTI being turned on. RTTI is part of the language standard but C++ turns it off by default. Change your project settings to enable RTTI and you will get rid of the compile-time warning and the run-time exception.

Re: typeid operator

kfaday19-Apr-04 13:35

19-Apr-04 13:35

that did it!!!!!!!!!!!!!1

thanks!!

Re: typeid operator

toxcct19-Apr-04 8:31

19-Apr-04 8:31

you deference a pointer when you don't get the address it contains but when you get what is at the pointed address.

<font style="color:blue;">char</font>* pc = (<font style="color:blue;">char</font>*)malloc(<font style="color:blue;">sizeof</font>(<font style="color:blue;">char</font>));     <font style="color:green;">// my pointer (something like 0x0A78DQ43)</font>
*pc = 'a';                                  <font style="color:green;">// dereferenced pointer (acsii code for 'a' caracter)</font>

 
 pc : simple pointer (cointaining an address)
*pc : dereferenced pointer (value at the pointed address)

TOXCCT >>> GEII power

Responding to messages raised by another process

Member 103146319-Apr-04 3:51

19-Apr-04 3:51

Hi all,

Is there a way to respond to an external function call raised by another process without having to modify the callees's code?

Thanks.

Re: Responding to messages raised by another process

toxcct19-Apr-04 4:14

19-Apr-04 4:14

the "raising" process must send its PID however you won't be able to know who sent you such message.

TOXCCT >>> GEII power

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