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Hi!
I have an array of pointers, which point to classes derived from the same class. I also have a pointer, that points to the array. Is there a simple way to find out to which element of the array this pointer points to, or shall i use a variable in the base class for this purpose?
Thanks
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You may use RTTI [^].
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
[My articles]
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Actually, this solves another problem of mine, so thanks a lot  However, I'd like to know, whether the pointer points to the 2nd, 5th, nth element of the array. If I understand the description correctly, type_info only gives me the name of the class my pointer-in-the-array points to (right?). First I thought of using sizof(), but my derived classes are of different sizes.
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Please post the relevant code (I need to know the pointer relationship with the array).
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
[My articles]
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I have a base class, let's say Car, and derived classes BMW, Mercedes, Renault, etc.
The array is: Car* p_Cars[2][16];
The pointer: Car** pCar;
for (int i = 0; i < 2; i++)
{
for (int j = 0; j < 16; j++)
{
if (j==2 || j==3)
p_Cars[i][j] = new BMW(i, j);
else if (j==4 || j==5)
p_Cars[i][j] = new Mercedes(i, j);
.
.
.
}
}
So I'd like to know, whether I can determine the element from its address.
I hope you understand my problem, i tried my best 
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A given value of pCar refers to the element p_Cars[i][j] (i.e. pCar == &p_Cars[i][j] holds true), provided i,j are computed as follows:
int k = (int) (pCar - &p_Cars[0][0]);
int i = k / 16;
int j = k % 16;
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
[My articles]
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You are welcome.
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
[My articles]
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So....you have:
CBase* pArray[] = { whatever... };
CBase* pItem = address_of_some_item_in_the_array;?
In that case:
const size_t index = pItem - pArray;
Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p
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Hi,
May i know how to check if a folder or file exists and if not create a folder....
im using ...
CString csPath1="C:\\Temp\\myfolder";
if(_access (csPath1+_T("\\Test"), 0)==-1);
::CreateDirectoryW(csPath1+L"\\Test",NULL);
and im getting the below error....
'_access' :cannot convert parameter 1 from 'ATL::CStringT<BaseType,StringTraits>' to 'const char *'...
Please help me......(myproject is in unicode)
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Why do you need to check first?
CreateDirectory will return ERROR_ALREADY_EXISTS if the directory already exists.
«_Superman_»
I love work. It gives me something to do between weekends.
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Thanks for ur help and please let me know how can i check whether a file(not directory) exists....(my project is in unicode)........
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You can use PathFileExists()[^] function (works with both folders and files).
The page contains a sample as well - saves me from typing code. Do remember to include shlwapi.h and link to shlwapi.lib.
It is a crappy thing, but it's life -^ Carlo Pallini
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How can I use DLL file in C#.NET ? I create dll in Borland C++ Compiler 5.5.1 and using C language.
Following code is not work.
My C Code;
-----------------------------------------------------
//hello.dll
#include <windows.h>
extern "C"
{
void __declspec (dllexport) function1()
{
MessageBox (NULL, "test message","test title",0);
}
}
BOOL WINAPI DllMain (HINSTANCE, DWORD, LPVOID)
{
return TRUE;
}
My C# Code;
-----------------------------------------------------
[DllImport("C:\hello.dll")]
public static extern void function1();
private void button1_Click(object sender, EventArgs e)
{
function1();
}
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Ok, I try this; But I get this error: Entry Point Not Found
C DLL CODE
-----------------------------------------------
#include <windows.h>
BOOL __stdcall DllMain(HINSTANCE hInst, DWORD dwReason, LPVOID lpReserved) {
return TRUE;
}
__declspec(dllexport) void __stdcall Message(char* p_szMessage) {
MessageBox(NULL, p_szMessage, "Message from DLL", MB_OK);
}
C# DLL CODE
-----------------------------------------------
[DllImport("filename.dll")]
static extern void Message(string msg);
private void button1_Click(object sender, EventArgs e)
{
Message("Hello world");
}
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What does it mean, specifically, 'it doesn't work' (i.e. more details needed)?
BTW you possibly would get better help at C# forum.
BTW2: I saw you've already cross-posted your question... 
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
[My articles]
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cross-posted is forbidden? Because this question related about between c and c#.
How can I "dumpbin -exports dll" in borland c++ 5.5.1 compiler on command prompt?
Do you have any idea?
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Hi,
how do we send structure data on tcp socket ?
any code snippets ?
Jalsa
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jalsa G wrote: how do we send structure data on tcp socket ?
Just like any other binary data.
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
[My articles]
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It doesn't matter what you're sending, just make sure the size of data is mentioned correctly.
You may need to typecast the data as char* 'cause that's what the function accepts.
«_Superman_»
I love work. It gives me something to do between weekends.
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«_Superman_» wrote: It doesn't matter what you're sending
Provided you're not sending pointers... 
--Carlo the Nitpick.
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
[My articles]
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Also, an old Greek mythic legend states that you cannot (and should not) send tomatoes on socket.
It is a crappy thing, but it's life -^ Carlo Pallini
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Rajesh R Subramanian wrote: Also, an old Greek mythic legend states that you cannot (and should not) send tomatoes on socket.
Of course, since old Greeks did not know both of tomatoes and sockets.
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
[My articles]
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Hello All,
I want to add Message handler for a generic class in Visual Studio 2008(VC++).
I have a generic class suppose CDataDisplay, Which don't having any base class. I want to create message map for this class.
How can i do this? If anyone having idea please help with some code.
Thanks,
Abhijit
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