C / C++ / MFC

26-Jul-06 5:03

Are you compiling as 64-bit by chance? I believe size_t is a 64-bit integer on 64-bit platforms whereas DWORD (which is just an unsigned long) is always 32-bits. Thus, if you try to implicitly cast a size_t to a DWORD, it will give you that warning. To get around it, either ignore it, use bitshift operations to get the lower 32-bits, or use static_cast to explicitly cast it to a DWORD.

If you decide to become a software engineer, you are signing up to have a 1/2" piece of silicon tell you exactly how stupid you really are for 8 hours a day, 5 days a week

Zac

conversion

RockyJames26-Jul-06 4:32

RockyJames

26-Jul-06 4:32

hi
i have funtion named change(long lngNo,unsigned char* pData);

where some times i send intger data,float data ,BOOL data as second parameter.How do i convert integer ,float ,BOOL to unsigned char*.

thanks in before

james

David Crow26-Jul-06 4:45

26-Jul-06 4:45

RockyJames wrote:
How do i convert integer ,float ,BOOL to unsigned char*.

Use the address-of operator (&). For example:

int x;
change(5L, &x);

"Money talks. When my money starts to talk, I get a bill to shut it up." - Frank

"Judge not by the eye but by the heart." - Native American Proverb

RockyJames26-Jul-06 4:53

RockyJames

26-Jul-06 4:53

error C2664: : cannot convert parameter 2 from 'int *__w64 ' to 'unsigned char *'

David Crow26-Jul-06 5:03

26-Jul-06 5:03

You'll need to cast it, since change() is expecting an unsigned char *.

Why are you trying to make a one-size-fits-all function?

"Money talks. When my money starts to talk, I get a bill to shut it up." - Frank

"Judge not by the eye but by the heart." - Native American Proverb

toxcct26-Jul-06 5:05

toxcct

26-Jul-06 5:05

can't you write several overloads of the function, which every func receive the right type ?

TOXCCT >>> GEII power

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Zac Howland26-Jul-06 5:13

26-Jul-06 5:13

RockyJames wrote:
i have funtion named change(long lngNo,unsigned char* pData);

where some times i send intger data,float data ,BOOL data as second parameter.How do i convert integer ,float ,BOOL to unsigned char*.

It is very bad practice to write a one-size-fits-all function. If you are trying to do something with the bytes (i.e. send them across a network using sockets), that is one thing, but if you are trying to decrease the number of methods you need to write for a given operation that doesn't involve direct byte transmissions, then this is the wrong approach.

A cleaner way of doing it would be to:

typedef unsigned long ulong;
typedef unsigned char byte;
// hide this method so that it isn't exposed
void change(ulong size, byte* data)
{
	// do something with data
}

// this is the exposed method
template<class T> void change(const T& data)
{
	change(sizeof(T), (byte*)&data);
}

If you decide to become a software engineer, you are signing up to have a 1/2" piece of silicon tell you exactly how stupid you really are for 8 hours a day, 5 days a week

Zac

RockyJames26-Jul-06 16:00

RockyJames

26-Jul-06 16:00

The function is not written by me,it is one of the function in control.that`s the problem..so how can i send integer ,float ,BOOL in BYTE or unsinged char format.....?

Zac Howland26-Jul-06 19:14

In C++, how get the value and key in the IDictionary

26-Jul-06 19:14

If you have the ability to refactor the function, you should.

That said, if you are just looking to get something working with it, you can cast anything in memory to a char* (or anything else for that matter) by taking the address of it (note that it is not necessarily safe to do, but is possible):

struct MyStruct
{
// some stuff here
};

MyStruct data;
change((char*)&data, sizeof(MyStruct));

If you decide to become a software engineer, you are signing up to have a 1/2" piece of silicon tell you exactly how stupid you really are for 8 hours a day, 5 days a week

Zac

chenxiujie26-Jul-06 4:19

chenxiujie

26-Jul-06 4:19

In C++, how get the value and key in the IDictionary

Thanks.

Re: In C++, how get the value and key in the IDictionary

David Crow26-Jul-06 4:33

Start a powerpoint slideshow from C++ (.pps file)

26-Jul-06 4:33

Are you referring to the Keys and Values properties?

"Money talks. When my money starts to talk, I get a bill to shut it up." - Frank

"Judge not by the eye but by the heart." - Native American Proverb

Remco Hoogenboezem26-Jul-06 3:54

Remco Hoogenboezem

26-Jul-06 3:54

Hi I would like to start a powerpoint slideshow from C++ the way it is done by the shell. I think this is possible by using OLE automation but I could not find a good example to help me on the way. I prefere to use slideshow viewer only if this is possible. (don't use powerpoint) I am not using MFC.

Thanks: cool:

Re: Start a powerpoint slideshow from C++ (.pps file)

David Crow26-Jul-06 3:59

Re: Start a powerpoint slideshow from C++ (.pps file)

26-Jul-06 3:59

Remco Hoogenboezem wrote:
Hi I would like to start a powerpoint slideshow from C++ the way it is done by the shell.

Then use ShellExecute().

"Money talks. When my money starts to talk, I get a bill to shut it up." - Frank

"Judge not by the eye but by the heart." - Native American Proverb

Hamid_RT26-Jul-06 5:24

Hamid_RT

26-Jul-06 5:24

See ShellExecute[^]

WhiteSky

Including an SDI in a Dialog based project

cv_k3n26-Jul-06 3:41

cv_k3n

26-Jul-06 3:41

Is it possible for me to link an SDI in my dialog based application? For example, when a button in the dialog is clicked, an SDI window comes up.

I've tried to 'File->Add->New Project' and added an SDI project into my current project but i have no idea how to link them up.

Cedric Moonen26-Jul-06 3:44

Cedric Moonen

26-Jul-06 3:44

You mean start a new application (which is a SDI) ?
If yes, take a look at the FAQ[^]

Cédric Moonen
Software developer

Charting control

cv_k3n26-Jul-06 3:55

cv_k3n

26-Jul-06 3:55

No, not opening a different application but opening an SDI window from an SDI project which i included in my current Dialog based project

Cedric Moonen26-Jul-06 4:01

Cedric Moonen

26-Jul-06 4:01

From your first post:

cv_k3n wrote:
I've tried to 'File->Add->New Project' and added an SDI project into my current project but i have no idea how to link them up.

This will simply create a new project (so, a new executable) that will be added in your solution. They are unrelated and the only way to 'link' them is to have one execute the other one. So, this is not the solution.

I don't know how you could do this but you'll probably have to do everything manually (create a frame window, create the view and the document, ...). But I'm not sure if this will work.

Cédric Moonen
Software developer

Charting control

Zac Howland26-Jul-06 4:10