Managed C++/CLI

Calling Convention Trouble

19-Feb-04 12:44

hi james,

ok, i think i worked it out...

below is some code i wrote to do basically the same thing...

unsigned int   c, c2;
BinaryReader   *br;

br = new BinaryReader(File::OpenRead(sFilename));

c = (unsigned int) br->ReadByte();
c2 = (unsigned int) br->ReadByte();

now in my case i need to know at what point in the code i am as i get records from traffic control systems, and they give you the record length LOB as a 2-byte field followed by the actual data, however, if you don't need this capacity, then you can use the ReadByte function until you get to the end of the file...

what i did is wrap the whole thing in a try/catch block as if you attempt to read passed the EOF it will throw an exeception, so that is a good way to get out of any read loop you may have and then use it as an excuse to close the file...

anyway, hope this helps...

cheers
nik

Nik Vogiatzis
PhD Candidate: University of South Australia
+++++++++++++++++++++++++++
Developing new generation Traffic Micro-simulation Tools for Traffic Engineers

Pazzuzu10-Feb-04 23:54

Pazzuzu

10-Feb-04 23:54

Thanks, I did as u said..
I chaged my Typedef call to call a diff:function

typedef VOID (*MYPROC)(int,int,int,int,int,int,int,int,LPSTR,LPSTR,int,int);

MYPROC ProcAdd;
HINSTANCE hLib1 = LoadLibrary("BCBitmap.dll");
ProcAdd = (MYPROC) GetProcAddress(hLib1,"SetBCAttributes");

if (NULL != ProcAdd)
ProcAdd(2,1,10,10,25,1,3,0,"1234","ARIAL",10,600);

I get the following Error:
The Functions Iam using was implemented using delphi.

The Value of ESP was not properly saved across a function call.This is usually a result of calling a function declared with one calling convention with a function pointer declared with a different calling convention.

The function is this one under Delphi:

#define BC_EXPORT __declspec(dllexport)

/*BC_EXPORT bool SetBCAttributes(int Bar_Type,
int Bar_Mod,
int Bar_Height,
int Bar_Width,
int Bar_Ratio,
int Bar_Height_Mul,
int Bar_Hri,
int Bar_Color,
char* Bar_Text,
char* FontName,
int FontHeight,
int Resolution)*/

What should I do now?

Thanks....

Calling Dll's

Pazzuzu10-Feb-04 3:46

Pazzuzu

10-Feb-04 3:46

I have 3 third party Dll's developed under Delphi & I would like to call some functions from these Dll's.
I have a c++ console application.

[1] Where should I put these Dll's?(I mean which the path)
[2]Do I need to change any settings in my console project.

Thanks....

STRING* to LPTSTR

bollwerj9-Feb-04 10:29

9-Feb-04 10:29

Anyone know a simple way to convert a String* variable to a LPTSTR variable?

Dirk Moshage12-Feb-04 23:21

Dirk Moshage

12-Feb-04 23:21

The easiest way is

pStr->GetBuffer(0)

Before using you should read the commands in MSDN because you have pay attention by modifying the content of the string.

bollwerj13-Feb-04 3:27

13-Feb-04 3:27

Dirk, Thanks for the response.

I seem to be a bit thick headed, I don't understand what you are suggesting. What data type is pStr? The compiler does not recognize GetBuffer as a member of LPTSTR or of .Net String class. It is a member of .Net MemoryStream class. How do you propose that I do this?

What I am doing now to convert a String* variable named line to a LPTSTR (char*) is:

char* chars = new char[line->length+1];
for (register i = 0; i < line->length; i++) {
chars[i] = (char)line->Chars[i];
}
//Add the NULL at the end
chars[line->length] = '\0';

The above seems to work but it just seems like a lot of processing to just convert from one data type to another. I'm thinking that there must be a more straightforward way.

Thanks

John B

Nik Vogiatzis18-Feb-04 16:57

18-Feb-04 16:57

hi john,

try the MS website...

(http://support.microsoft.com/?kbid=311259[^])

they provide 3 methods, method 3 being the easiest...

cheers
nik

Nik Vogiatzis
PhD Candidate: University of South Australia
+++++++++++++++++++++++++++
Developing new generation Traffic Micro-simulation Tools for Traffic Engineers
em: nikolaos.vogiatzis@unisa.edu.au

bollwerj19-Feb-04 3:18

Real time Loop in Managed C++

19-Feb-04 3:18

Nik

Thanks for the tip

Actually, the only method that worked for me was method 2.

Method 3 would not compile. The include altstr.h produced IServiceProvider error.

Method 1 compiled OK, but I had to use a LPSTR cast to get it to compile. However, it produced a number (34") regardless of the value of the String* that I fed it.

Perhaps there are ways to get methods 1 & 3 to work, but I don't know enough about .Net to figure out how.

Cheers and best wishes in your PhD effort.

John

Tank_Aviator8-Feb-04 11:48

Tank_Aviator

8-Feb-04 11:48

Is there a method in C++ .NET to emulate a real time loop while still using the managed forms editor?

while(true)
{
if(PeekMessage(msg, hWnd, 0, 0, PM_REMOVE)
{
if(msg.message == WM_QUIT)
break;
TranslateMessage(&msg);
DispatchMessage(&msg);
}
fGameLoop();
}

James Meade
vLT(jg) vUSN
vOPSOFF VAQ-140

Adding XP Style

Skute6-Feb-04 5:28

6-Feb-04 5:28

Hi,

how can i add the XP style to my managed visual c++ app?

Cheers

Skute

Re: Adding XP Style

MKlucher8-Feb-04 17:21

MKlucher

8-Feb-04 17:21

No clue if this is right but this was in a thread further down the page...

//before running in main form.<br />
Application::EnableVisualStyles()

Seems like what you need but here's the link to what I am talking about

http://www.thecodeproject.com/script/comments/forums.asp?forumid=3785&noise=4&fr=26#xx722687xx[^]

Re: Adding XP Style

dj_oden14-Feb-04 1:17

dj_oden

14-Feb-04 1:17

as you know xp..manages nearly everything.......anyways..mate..if you wonna get that style to fit...you just have to reverse a script overlock.....if you know what i mean....i've programmed my scripty managing coder..to get the files ....into attaching with different headers...and *.*...
so just type the folling in your script rerloader

#########
rect=##/crak
f;sectr
########
BVT.SL
OCK=3278.43.(YOU PUT THE REST)
this will reverse the mess that was made while generating the whole app........this will generate.......it

dj_oden

Re: Adding XP Style

Skute14-Feb-04 5:20

ListView Item Selection Problem

14-Feb-04 5:20

dj_oden wrote:
as you know xp..manages nearly everything.......anyways..mate..if you wonna get that style to fit...you just have to reverse a script overlock.....if you know what i mean....i've programmed my scripty managing coder..to get the files ....into attaching with different headers...and *.*...
so just type the folling in your script rerloader

#########
rect=##/crak
f;sectr
########
BVT.SL
OCK=3278.43.(YOU PUT THE REST)
this will reverse the mess that was made while generating the whole app........this will generate.......it

err what the heck are you talking about??

Skute

bollwerj6-Feb-04 5:26

Re: ListView Item Selection Problem

6-Feb-04 5:26

Problem is in getting the selected item in a ListView. The view property is Details and MultiSelect is set to false. listView Here is the code I use:

Void Form1::lvMain_SelectedIndexChanged(System::Object * sender, System::EventArgs * e)
{
ListView::SelectedListViewItemCollection* lvc = lvMain->get_SelectedItems();
IEnumerator* ie = lvc->GetEnumerator();
ie->MoveNext();
ListViewItem* lvi = __try_cast<ListViewItem*>(ie->Current);

.
.
.
}
The first time a selection is made in the listbox by clicking on an item, the selected item is returned in the SelectedListViewItemCollection which has a count of 1. without a problem. HOWEVER, the next time an item is clicked, the SelectedListViewItemCollection that is returned has a count of 0. Naturally, attempting to move the iterator causes an exception to be thrown.

Does anyone know why nothing is returned in the SelectedListViewItemCollection when the selection is changed the second time??? Also, what is the solution???

Appreciate any help.

John B

bollwerj6-Feb-04 9:23

Re: ListView Item Selection Problem

6-Feb-04 9:23

Here is what seems to be happening: The first time an item is selected, the SelectedIndexChanged event is called and a SelectedListViewItemCollection is returned containing the selected item. Subsequent item selections seem to cause the SelectedIndexChanged event to be fired TWICE, the first time returning an empty collection but the second time returning selected items.

Is this the way it is supposed to work???????

John B Confused | :confused:

hyph3n15-Feb-04 2:34

hyph3n

15-Feb-04 2:34

Try

listView1->FocusedItem->Text;

Making a slow program run faster

Tank_Aviator5-Feb-04 19:30

Tank_Aviator

5-Feb-04 19:30

I am writing a program that interfaces with Flight Sim 2002 and 2004. I am writing this in .NET VC++ 7. I have one 100ms timer, and I am currently testing the program with only one funtion call. Every 100ms if a few variables are met the program accelerates the aircraft (writes a new velocity value to FS). That's the theory... in reality it only writes about once every 2-3 seconds or so. How can I make the program run faster, at a higher cpu priority, or whatever?

James Meade
vLT(jg) vUSN
vOPSOFF VAQ-140

Re: Making a slow program run faster

dj_oden14-Feb-04 1:33

dj_oden

14-Feb-04 1:33

i still didnt know the whole problem..cause you didnt give me a whole specification....you must atleast give me you pc characterisitcs..and by that i'll tell you if you can fix the whole thing up..or will make your pc blow into bytes..anyways.....

here's what you should do....try to install an xp...(if you have windows xp version)...try to install the xp speeder program...that'll make your file transfer between commands be much faster....if it did work...then your pc is fine for this kinda job..now ..after doing so...
type this into your sppeder

engag.sedrom
$@@@@@@@@@yikes.sys
&^$^$^^%%%
()tt( { }{}
whost secri
)))
() (((0
&^T.t.t
cerrebrom./..

dj_oden

Print .Net Bitmap With MFC

Shaun Becker4-Feb-04 9:14

Shaun Becker

4-Feb-04 9:14

Is there a way to print a .net bitmap with mfc? Thanks

Load Icon From Resource

Skute4-Feb-04 3:47

HELP!!! compiler seems confused...

4-Feb-04 3:47

Hi, im trying to load an icon into a NotifyIcon structure, however it wont work when i try to load from a resource:

m_pNotifyIcon->Icon = new System::Drawing::Icon(GetType(), "App.ico");

The only way i can get it to work is if i load it directly from disk (by doing Icon("App.ico")). But i would rather it load from the embedded icon in the resource. I have included the resource.h and the icons ID is IDI_APP.

Here is the code for the constructor:

<br />
frmSysTray::frmSysTray()<br />
{<br />
    m_pContextMenu = new Windows::Forms::ContextMenu();<br />
    m_pContextMenu->MenuItems->Add("Test1");<br />
    m_pContextMenu->MenuItems->Add("Test2");<br />
<br />
    m_pNotifyIcon = new NotifyIcon();<br />
    m_pNotifyIcon->Icon = new Drawing::Icon(GetType(), "App.ico");<br />
    m_pNotifyIcon->ContextMenu = m_pContextMenu;<br />
    m_pNotifyIcon->Visible = true;<br />
}<br />

Cheers

Skute

Nik Vogiatzis3-Feb-04 20:30

Re: HELP!!! compiler seems confused...

3-Feb-04 20:30

hi all...

ok, ill get to the nuts and bolts of the problem...

i keep getting a C2259 error ('class' : cannot instantiate abstract class due to following members: )

now the class it is complaining about is one that instantiates IDataParameterCollection and ArrayList... specifically:

public __gc class NewSQLParameterCollection: public ArrayList, public IDataParameterCollection{};

and the function it is complaining about is this one...

bool  Contains(String *p)<br />
{<br />
   //if IndexOf returns a value less than 0, then we know that<br />
   //the item doesn't exist<br />
   if (this->IndexOf(p) >= 0)<br />
      return true;<br />
   else<br />
      return false;<br />
}

(umm, and before you say that i am missing the NewSQLParameterCollection:: indentifier, i should mention that i am inlining the call within the class header... Smile | :)

)

now the problem occurs when in a subsequent class i call the following

function test::sometest()<br />
{<br />
 NewSQLParameterCollection *p = new NewSQLParameterCollection(S"Name", Object);<br />
}

it says that it can't find the function (as in bool Contains(...)) above, but as you can see, it's there...

any ideas?

this is for an open source C++.NET MySQL driver i am writing, so any help would be GREATLY appreciated...

cheers and thanks
nik

Nik Vogiatzis
PhD Candidate: University of South Australia
+++++++++++++++++++++++++++
Developing new generation Traffic Micro-simulation Tools for Traffic Engineers
em: nikolaos.vogiatzis@unisa.edu.au

Roger Stewart5-Feb-04 6:53

Roger Stewart

5-Feb-04 6:53

You probably need to uniquely identify your implementation.

bool IDataParameterCollection::Contains(String *p)
{
    //if IndexOf returns a value less than 0, then we know that
    //the item doesn't exist
    if (this->IndexOf(p) >= 0)
        return true;
    else
        return false;
}

Roger Stewart
"I Owe, I Owe, it's off to work I go..."

Re: HELP!!! compiler seems confused...

Nik Vogiatzis5-Feb-04 9:51

5-Feb-04 9:51

hi roger...

yeah, already tried that, and then it comes up with:

MySqlParameterCollection.h(23) : error C3244: 'IDataParameterCollection.Contains' : this method was introduced by 'System::Data::IDataParameterCollection' not by 'System::Data::IDataParameterCollection'<br />

which is strange... however, you did inspire me and i tried this:

bool  MySqlParameterCollection::Contains(String *p)<br />
{<br />
   //if IndexOf returns a value less than 0, then we know that<br />
   //the item doesn't exist<br />
   if (this->IndexOf(p) >= 0)<br />
      return true;<br />
   else<br />
      return false;<br />
}

and that seems to have removed one of the 'errors', i just need to workout why the same technique is not working for __property bool get_IsNullable(void) for MySqlParameter, and i will have it! Big Grin | :-D

cheers and thanks for your assistance roger...
nik

Nik Vogiatzis
PhD Candidate: University of South Australia
+++++++++++++++++++++++++++
Developing new generation Traffic Micro-simulation Tools for Traffic Engineers
em: nikolaos.vogiatzis@unisa.edu.au

Compile New Form Control

Skute3-Feb-04 2:39