Managed C++/CLI

Re: How to read a pdf file using c++

7-Mar-06 22:14

Allang Garder wrote:
using c++.

do you know this is the Managed C++ forum (for .NET framework so) ?

prrusa8-Mar-06 9:14

prrusa

8-Mar-06 9:14

How would you do it in cli? I would
be interested.

Help with this basic code

Fu Manchu7-Mar-06 13:56

Fu Manchu

7-Mar-06 13:56

hi, i am having some trouble with this basic example code, i can't figure out why i am getting an error, null reference!

please help

thanks

#include "stdafx.h"<br />
<br />
#using mscorlib.dll<br />
using namespace std; <br />
<br />
<br />
class Foo<br />
{<br />
public:<br />
 Foo();<br />
 ~Foo();<br />
void DoSomeFoo();<br />
};<br />
<br />
 // constructor<br />
Foo::Foo() <br />
  {<br />
	cout<<"Constructor called!"<<endl;<br />
  }<br />
//  // destructor<br />
Foo::~Foo() <br />
  {<br />
	cout<<"Destructor called"<<endl;<br />
  }<br />
<br />
  // some method<br />
  void Foo::DoSomeFoo()<br />
<br />
  {<br />
	  cout<<"Do something funny!"<<endl;<br />
	  cout<<"Burrrp!"<<endl;<br />
  }<br />
<br />
__gc class MFoo<br />
{	<br />
private:<br />
	Foo * _foo;<br />
public:<br />
	MFoo();<br />
	~MFoo();<br />
	void ManagedDoSomeFoo();<br />
};<br />
<br />
  // constructor<br />
MFoo::MFoo() <br />
	{<br />
	 _foo = new Foo();<br />
	}<br />
  // destructor<br />
MFoo::~MFoo()<br />
	{<br />
	 delete _foo;<br />
	}<br />
<br />
  // method<br />
void MFoo::ManagedDoSomeFoo() <br />
  {<br />
	  _foo->DoSomeFoo();<br />
  }<br />
<br />
<br />
int _tmain() <br />
{ <br />
<br />
<br />
	MFoo*myfoo;<br />
	myfoo->ManagedDoSomeFoo();<br />
<br />
    return 0; <br />
}

Re: Help with this basic code

toxcct7-Mar-06 21:45

Re: Help with this basic code

7-Mar-06 21:45

where in the code are you getting this error, and what does the error message say ?
does it happen at runtime or before ?

Gavin Taylor7-Mar-06 23:39

Gavin Taylor

7-Mar-06 23:39

Your never actually creating an instance of myfoo, try changing your _tmain to:

int _tmain() 
{ 
	MFoo*myfoo = new MFoo( ); // Create an instance of this object
	myfoo->ManagedDoSomeFoo();
	return 0; 
}

Gavin Taylor
w: http://www.gavspace.com

-- modified at 5:39 Wednesday 8th March, 2006

Re: Help with this basic code

Fu Manchu8-Mar-06 12:01

Fu Manchu

8-Mar-06 12:01

thanks guys, i thought it was something like that,but i mainly use vb.net so i get a little stuck with c++.

i have been trying to wrap this example, so i can practice for a much bigger program.

i have never done this before and the help on the net is a little vague, i need a very very basic walkthrough, because the ones i have found won't compile, and its hard enough trying to debug code that you dont really understand.

i know this much....

i have a class library(.net) called fooManaged and its automatical created fooManaged.h. and i created UnManaged.h

in the UnManaged.h file i have this code.....

#include iostream <br />
 #include vcclr.h<br />
using namespace std;<br />
<br />
class Foo<br />
{<br />
public:<br />
 Foo();<br />
 ~Foo();<br />
void DoSomeFoo();<br />
};<br />
<br />
 // constructor<br />
Foo::Foo() <br />
  {<br />
	cout<<"Constructor called!"<<endl;<br />
  }<br />
//  // destructor<br />
Foo::~Foo() <br />
  {<br />
	cout<<"Destructor called"<<endl;<br />
  }<br />
<br />
  // some method<br />
  void Foo::DoSomeFoo(void)<br />
<br />
  {<br />
	  cout<<"Do something funny!"<<endl;<br />
	  cout<<"Burrrp!"<<endl;<br />
  }

in fooManaged.h i have this code....

// fooManaged.h<br />
<br />
#pragma once<br />
using namespace System;<br />
<br />
namespace fooManaged<br />
{<br />
	public __gc class MFoo<br />
{	<br />
private:<br />
	Foo * _foo;<br />
public:<br />
	MFoo();<br />
	~MFoo();<br />
	void ManagedDoSomeFoo();<br />
};<br />
  // constructor<br />
MFoo::MFoo() <br />
	{<br />
	 _foo = new Foo();<br />
	}<br />
  // destructor<br />
MFoo::~MFoo()<br />
	{<br />
	 delete _foo;<br />
	}<br />
<br />
  // method<br />
void MFoo::ManagedDoSomeFoo() <br />
  {<br />
	  _foo->DoSomeFoo();<br />
  }<br />
<br />
}

the fooManaged.cpp file just has...

#include "stdafx.h"
#include "Unmanagedfoo.h"
#include "fooManaged.h"
#using mscorlib.dll

it all compiles...but there is a big linking error!!

Compiling...
fooManaged.cpp
Linking...
LINK : error LNK2020: unresolved token (0A000005) _CxxThrowException
LINK : error LNK2020: unresolved token (0A000019) free
LINK : error LNK2020: unresolved token (0A00001A) strlen
LINK : error LNK2020: unresolved token (0A00001B) memmove
LINK : error LNK2020: unresolved token (0A00001C) memcpy
LINK : error LNK2020: unresolved token (0A00001D) delete
LINK : fatal error LNK1120: 6 unresolved externals

i must be doing something wrong, some help with this will be very wecome

thanks

searchable void* container

Amr Shahin7-Mar-06 2:58

7-Mar-06 2:58

hi every1
will u plz help me on this ...
im creating a generic container class and im implemeting it using the (void*) pointer technique

but to add a search feature, the search function should compare two (void*) variables, i dont know how to do that!

i think memcmp could be used somehow but the problem that it needs a length parameter which is now available!!

thanks already

toxcct7-Mar-06 3:06

7-Mar-06 3:06

you are on the C++/CLI forum[^], while you question is for the Visual C++ forum[^]
next time, be careful...

and for you problem, do you code in C or C++ ?
because C++ provides templates, that may certainly interrest you...

Amr Shahin7-Mar-06 3:10

7-Mar-06 3:10

oh im sorry for this mistake

anyway it doesnt really matter if its a c or c++ but for templates they are not compliant with the c++ standard so i think using the void* will be safer!!

John M. Drescher7-Mar-06 3:15

7-Mar-06 3:15

Amr Shahin wrote:
oh im sorry for this mistake

It's an easy mistake to make unless you read the main forum page that explains the topic of each forum:

http://www.codeproject.com/script/comments/forums.asp[^]

John

toxcct7-Mar-06 3:16

7-Mar-06 3:16

Amr Shahin wrote:
ut for templates they are not compliant with the c++ standard so i think using the void* will be safer!!

are you on drugs ?! WTF | :WTF:

templates are part of and are defined in the standard !!!!!
hey,, i think you should really revise you judgement about templates, and learn a bit more about them...

John M. Drescher7-Mar-06 3:22

7-Mar-06 3:22

Amr Shahin wrote:
i think using the void* will be safer!!

Templates were not finalized until the mid to late 90s so compliers created before this may have a problem with them but as long as you stick to the basics and don't use partial template specialization and a few other features you will be fine on older compilers. I have been using templates for at least 5 years starting with VC6 (which is not fully compliant but very capable of using templates). void* is definitly not the way to go if you are using c++.

John

-- modified at 12:09 Tuesday 7th March, 2006

John M. Drescher7-Mar-06 3:12

7-Mar-06 3:12

It looks like most questions for this forum are off topic...

John

-- modified at 9:16 Tuesday 7th March, 2006

toxcct7-Mar-06 3:16

7-Mar-06 3:16

John M. Drescher wrote:
It looks like most questions for this forum are off topic...

true, but if people had a look at the admin note... D'Oh! | :doh:

John M. Drescher7-Mar-06 3:24

7-Mar-06 3:24

Although I have seen it in the lounge I did not even notice it in this forum today...

John

Nemanja Trifunovic7-Mar-06 5:46

Nemanja Trifunovic

7-Mar-06 5:46

John M. Drescher wrote:
It looks like most questions for this forum are off topic...

True, but i blame MS marketing for this. Most people consider CLI to be "command line interface", not "common language..." (what the heck is I for anyway?).

My programming blahblahblah blog. If you ever find anything useful here, please let me know to remove it.

toxcct7-Mar-06 5:51

Re: Print program in C only

7-Mar-06 5:51

Nemanja Trifunovic wrote:
(what the heck is I for anyway?).

Common Language Infrastructure... D'Oh! | :doh:

Print program in C only

patel mayur6-Mar-06 21:16

patel mayur

6-Mar-06 21:16

Hi Friends
I like to have a Print program that prints text files & having the following features only made in C language using win32 libraries :

1. When run, it needs to present a dialog with where you can select a text file for it to print.
2. There should be options on the dialog to specify how many 'virtual pages' it will print on one page (it should either be 1 (which fills the whole page), 2 (where they are rotated 90 degrees), or 4 (where they are printed using 4 regions of the page)) - this is similar to the old utility LaserLst:

http://fresh.t-systems-sfr.com/linux/src/laserprt.tar.gz:a/laserprt.c

3. It should use a fixed width font, and the user should be able to specify the font size.
4. There should be a print and a print preview button
5. There should be an option to make a black border around the 'virtual page'
6. At the top of each 'virtual page' (outside of the black border) it should show the filename on the upper left, and the page number (ie; 4 of 20) on the upper right.
7. There should be an option to turn on line number printing, in which case it would show the like number prior to the line being listed.

Regards,
Mayur Patel

Ingo6-Mar-06 23:19

Ingo

6-Mar-06 23:19

Sounds good. And it's even better that you have no questions how to write. So I'm looking forward to the programm. Please present it here. :->

Greetings,
Ingo

------------------------------
PROST Roleplaying Game

Re: Print program in C only

Professor Sharada Ulhas7-Mar-06 7:28

Professor Sharada Ulhas

7-Mar-06 7:28

mayur! ur confine my doubt abut the homework assignment and u make me sad by not homework working the doubt. now u will get back but low grade forur work which u doubt did. i will report this a student body. shame on u.

Sincelery yours, Computer Information conSciences Professor and grader, Sharada Ulhas

printing the address of a non static member function of a clss

Amr Shahin6-Mar-06 3:23

Re: printing the address of a non static member function of a class [edited]

6-Mar-06 3:23

hi everyone
im trying to check if my compiler creates a copy of the nonstatic member functions for each object or it just shares the code.
to do that i wrote this code:

/*******************************

#include <iostream>

using namespace std;

class cls
{
public:
int f( )
{
//cout << (void*)(f) <

toxcct6-Mar-06 3:34

Re: printing the address of a non static member function of a clss

6-Mar-06 3:34

firstly, you can be sure that the compiler shares only one copy of the member functions body.

but you could do this to test :

class cls {
    public;
    void f() {
    }
};
 
void main() {
    cls a, b;
    printf("%l %l", (void*)(&(a.f)), (void*)(&(b.f)));
}

-- modified at 13:19 Monday 6th March, 2006 (thanks Mike)

Amr Shahin6-Mar-06 3:51

Re: printing the address of a non static member function of a clss

6-Mar-06 3:51

the code u gave me didnt work!!

another thing
if the compiler always shares the space why would static functions exist in the first place???!!!

toxcct6-Mar-06 4:00