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That's quite dangerous to do so (specially when you delete the array). If you know the data type upfront, use a buffer of that type and stick to it, it will save you a lot of troubles.
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Thanks for your advice. Actually I think it is better to use the buffer gain and again, that mean dynamically initialization and delete is after use. As you say, no need to deal with dangerous situations and better to work with in right way.
Reuse of the buffer will helps me to work fine with the memory.
I appreciate your help all the time...
Eranga 
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Technically yes, but any time you need to read from or write to the void*, you'd have to cast it first. That's ugly and inefficient.
"Normal is getting dressed in clothes that you buy for work and driving through traffic in a car that you are still paying for, in order to get to the job you need to pay for the clothes and the car and the house you leave vacant all day so you can afford to live in it." - Ellen Goodman
"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne
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DavidCrow wrote: you'd have to cast it first. That's ugly and inefficient.
I agreed with you. When I deal with such instances easily can be misses those casting and stuff. Better to avoid such points in developments. 
I appreciate your help all the time...
Eranga
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The intialization in void is correct, you can after cast to other types.
For the second question...
If you are changing the size for every iteration... you must do it at the last line of your loop.
void* pBuffer = NULL;
for (int i = 0; i < numFiles; i++)
{
CFile f (a_szFileName[i], CFile::modeCreate | CFile::modeWrite);
pBuffer = new BYTE [(a_differentSizes[i])];
f.Write (pBuffer, (a_differentSizes[i] * sizeof (BYTE)));
delete [] pBuffer;
pBuffer = NULL;
}
If you are using a simple iteration to go through the buffer, you should logically write the creation and the deletion at the beggining and at the end of your working area respectively, not into the loop.
void* pBuffer = NULL;
pBuffer = new BYTE [nBufferSize];
for (int i = 0; i < nBufferSize; i++)
{
if (*(pBuffer + i) == "F")
}
delete [] pBuffer;
pBuffer = NULL;
was it what you wanted to know?
Greetings.
--------
M.D.V.
If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?
Help me to understand what I'm saying, and I'll explain it better to you
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Nelek wrote: The intialization in void is correct, you can after cast to other types.
Please if you can read my last replay for Cedric Moonen post. I have a suggestion.
Nelek wrote: pBuffer = NULL;
Actually my question is that, why you do this after free/delete the buffer. Is it required.
I appreciate your help all the time...
Eranga
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I have read Cedric's answer. I agree, but this doesn't mean is incorrect. If I know the format, I usually use the format. The code above was an example.
About the NULL after deleting, it actually is not a must, but it doesn't disturb at all, and I use it so, maybe to ensure that if I reuse the buffer, it won't go trhough ASSERT (pBuffer) by mistake because it still has the last address (although no datas in).
Greetings.
--------
M.D.V.
If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?
Help me to understand what I'm saying, and I'll explain it better to you
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Nelek wrote: About the NULL after deleting, it actually is not a must, but it doesn't disturb at all, and I use it so, maybe to ensure that if I reuse the buffer, it won't go trhough ASSERT (pBuffer) by mistake because it still has the last address (although no datas in).
That is really interesting pal. Actually those kind of hints are really helpful in a large project. Because I wont miss anything and not cause any damage in the future developments. 
I appreciate your help all the time...
Eranga
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Hi,
How to get the date and time of when the history was cleared in the PC.
Thanks in advance
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??
time_t GetTime( ) const;
but, what do u mean with that "history"?
Greetings.
--------
M.D.V.
If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?
Help me to understand what I'm saying, and I'll explain it better to you
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I want to know the time when the IE history was cleared in the pc.
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I don't know how to get it, sorry. IExplorer is a big unknown for me (internal programming) yet.
Greetings.
--------
M.D.V.
If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?
Help me to understand what I'm saying, and I'll explain it better to you
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Do you know for a fact if it is actually stored somewhere, or are you just hoping/guessing?
"Normal is getting dressed in clothes that you buy for work and driving through traffic in a car that you are still paying for, in order to get to the job you need to pay for the clothes and the car and the house you leave vacant all day so you can afford to live in it." - Ellen Goodman
"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne
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Hi All,
I am new Activex project.
I want to make MFC Activex Control project in which I want to add DLL project as other project in the same solution.And I want to make this Activex project depends on this DLL project.Is it possible to do like this??
Plz give me any suggetion.
Thanks in Advance.
Ashish Bhatt
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what stops u in creating an activex object in ur dll project instead?
Prasann
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Hey Thanks For Reply,,
I want to add my other project as DLL because I want to make it as Hooks which contineusly sends message to my Activex project(Messages like Screen Update,Mouse Update).In my Activex project I want to get those messages and process on these messages.
Is this possible??
Anything you understand, Plz suggest me.
Thanks.
Ashish Bhatt
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Hi ALL,
Plz any have the code for socket programming in vc++ for dialog based application, in such a way that Receive should happen in 1 thread and send should happen through other thread.
plz help me
With Regards
Amjath
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Amjath Rahman wrote: Plz any have the code for socket programming in vc++ for dialog based application...
There are several listed here.
"Normal is getting dressed in clothes that you buy for work and driving through traffic in a car that you are still paying for, in order to get to the job you need to pay for the clothes and the car and the house you leave vacant all day so you can afford to live in it." - Ellen Goodman
"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne
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Dear all,
I want to know the length of some BYTE variable (unsigned char). Here I included snippet of the code:
#include <iostream><br />
#include <string><br />
<br />
using namespace std;<br />
typedef unsigned char BYTE_T;<br />
<br />
void printLen(BYTE_T *ld_pbyteTemp);<br />
<br />
int main(int argc, char *argv[])<br />
{<br />
BYTE_T *ld_pbyteChar = new BYTE_T[50];<br />
memset(ld_pbyteChar, 'a', 50);<br />
<br />
for(int i=0; i<50; i++) cout << "i = " << i << " -> " << ld_pbyteChar[i] << endl;<br />
<br />
printLen(ld_pbyteChar);<br />
<br />
return 1;<br />
}<br />
<br />
void printLen(BYTE_T *ld_pbyteTemp)<br />
{<br />
int ld_intLen = sizeof ld_pbyteTemp;<br />
cout << "Length = " << ld_intLen << endl;<br />
}
Is there anyone know how to get the length of the "ld_pbyteTemp" in function printLen?
Thanks before...
Regards,
Ian
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try:
int ld_intLen = sizeof(*ld_pbyteTemp);
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Llasus wrote: int ld_intLen = sizeof(*ld_pbyteTemp);
It didn't work. It return 1 not 50 as expected.
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Oops, sorry I didn't notice that. As the others explained you can't obtain it just by using sizeof. You can get the size that you want only thru some changes. instead of unsigned char you can use char. And instead of sizeof() use strlen(ld_pbyteTemp). I don't know if you'd want to change your variable though. Anyway its a simpler workaround if you really want to get the size.
Just another thing though. Since it is a char end the last element with NULL.
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you can't. there's no safe way to get the size of a dynamic array in C/C++.
you must either pass the size of the allocated data along with the pointer, or use a container class (like std::vector) that keeps track of it for you.
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