C / C++ / MFC Discussion Boards

ForNow9-Feb-17 2:05

9-Feb-17 2:05

Thanks for your help my code as seems to be posting messages i added the ChaneWindowMessageFilterEx per jochen don't know if It's needed if posting in the same process and it seems that my messages to delivered

Deleting Image IN VC++

raajpatel7-Feb-17 23:14

raajpatel

7-Feb-17 23:14

Hi,
I am working in vc++ mfc and i have been stuck some where I want to overwrite a selected Image in a particular path. Please help out me

Re: Deleting Image IN VC++

Jochen Arndt7-Feb-17 23:28

Jochen Arndt

7-Feb-17 23:28

raajpatel wrote:
I want to overwrite a selected Image in a particular path

That is rather unclear. Please edit your question and be more specific.

Are you referring to an image file stored on the disk with known path and file name?
What is the image source that you want to store (another file, a bitmap in memory)?
What image format should be used (BMP, JPG, TIFF, PNG)?

Re: Deleting Image IN VC++

raajpatel8-Feb-17 0:47

raajpatel

8-Feb-17 0:47

Hi,
I want to replace same image and over same path with resized on a disk and format is "gif" file

Re: Deleting Image IN VC++

Jochen Arndt8-Feb-17 0:54

Jochen Arndt

8-Feb-17 0:54

You can use the CImage Class[^]. Use the Save() function with ImageFormatGIF to save the image as GIF.

How to create the CImage depends on the source. It can be loaded from file or passed an existing in memory bitmap.

Re: Deleting Image IN VC++

CPallini7-Feb-17 23:50

CPallini

7-Feb-17 23:50

'An image on a particular path' sounds like a file, to me. To overwrite the file, open it for writing and do write the new image data to it.

IM chat question

Tracy Software5-Feb-17 21:17

Tracy Software

5-Feb-17 21:17

Hi All,

I'm trying to create Instant Messaging software for Windows.
What are the options for the core chat technology?

Is Microsoft Bot Framework a good choice for one-one chat?
Its planed for man-bot so not sure about that...

In addition I don't want to implement it from the ground, WINSOCK etc

I prefer use an already tested platform or library for that
Is DCOM or MSMQ a good choise ?


please advice
mithrhill

modified 6-Feb-17 3:58am.

Coding on hostel mannagement in c program

Member 129807512-Feb-17 21:39

Member 12980751

2-Feb-17 21:39

Hello,
I am a BCA student.I want to know about project on hostel mannagement system in c program with their source code.
Any one please send me the source code to my email:- chandanbhoi11@gmail.com

Re: Coding on hostel mannagement in c program

Jochen Arndt2-Feb-17 22:27

Jochen Arndt

2-Feb-17 22:27

CodeProject is not a code writing service. See also the sticky post (actually) above yours:

Quote:
2. Be specific! Don't ask "can someone send me the code to create an application that does 'X'. Pinpoint exactly what it is you need help with.
11. If you have a school or university assignment, assume that your teacher or lecturer is also reading these forums.

We will help if you got stuck at specific portions of your code. But if you need code written for you, you probably have to hire someone and pay for it.

Re: Coding on hostel mannagement in c program

Afzaal Ahmad Zeeshan2-Feb-17 22:34

Afzaal Ahmad Zeeshan

2-Feb-17 22:34

Also, we do not do the assignments for students and it will be against our rules and will not help you in any way. The assignments are assigned to you to help you focus on programming.

If you are having trouble, consult your teacher and ask him to guide you in the process so that you can do it. If you still face issues, try group study and talk about the problem in the group and ask help from peer students.

However, if you face any problem during the programming; such as errors occur, do come here and we will help a bit.

One more thing: Sharing the email online will only help spammers, who are always building their email databases, to send lottery win emails. You get the point, please do not share the emails on online forums. They are not safe.

The sh*t I complain about
It's like there ain't a cloud in the sky and it's raining out - Eminem
~! Firewall !~

Re: Coding on hostel mannagement in c program

Patrice T6-Feb-17 15:51

Patrice T

6-Feb-17 15:51

We do not do your HomeWork.
HomeWork is not set to test your skills at begging other people to do your work, it is set to make you think and to help your teacher to check your understanding of the courses you have taken and also the problems you have at applying them.
Any failure of you will help your teacher spot your weaknesses and set remedial actions.
So, give it a try, reread your lessons and start working. If you are stuck on a specific problem, show your code and explain this exact problem, we might help.

As programmer, your job is to create algorithms that solve specific problems and you can't rely on someone else to eternally do it for you, so there is a time where you will have to learn how to. And the sooner, the better.
When you just ask for the solution, it is like trying to learn to drive a car by having someone else training.
Creating an algorithm is basically finding the maths and make necessary adaptation to fit your actual problem.

Patrice

“Everything should be made as simple as possible, but no simpler.” Albert Einstein

I tried PostMessage as well

ForNow2-Feb-17 16:17

ForNow

2-Feb-17 16:17

I was told PostMessage would work for IPC the child process never gets control

Re: I tried PostMessage as well

Victor Nijegorodov2-Feb-17 22:03

Victor Nijegorodov

2-Feb-17 22:03

How do you use it?
What message ID do you use?

Re: I tried PostMessage as well

leon de boer2-Feb-17 23:48

leon de boer

2-Feb-17 23:48

The child probably wont see the message because the parent isn't passing it up. Very few messages are passed from a parent to a child unless you specify it beyond the obvious stuff like keyboard and mouse. Depending on the ID it isn't clear to me a message will be passed to a child window I need to know more about the window types and flags involved.

In vino veritas

modified 3-Feb-17 5:59am.

IPC Thru WM_COPYDATA

ForNow2-Feb-17 15:52

ForNow

2-Feb-17 15:52

Hi
I have been having intermittent problems notifying a child window process with SendMessage

So I decided to go with the Microsoft Sanctioned way WM_COPYDATA

In my console Parent process I do GetConsoleWindow (which I observe returns what seems

a valid HWND),

I declare a COPYDATASTRUCT member on the stack (locally)

and do SendMessage I have gotten the child window HWND with FindWindow

in my MFC child window I have a messagemap entry

and nothing it never gets there I am running under both the console app and the MFC app

under Visual studio debugger so I can see what's going on

C++

ON_MESSAGE(WM_COPYDATA,Debug_it)

Re: IPC Thru WM_COPYDATA

Jochen Arndt2-Feb-17 21:36

Jochen Arndt

2-Feb-17 21:36

See the first comment at WM_COPYDATA message (Windows)[^]:

Quote:
Starting with Windows Vista, the application that is to receive the WM_COPYDATA message must call the ChangeWindowMessageFilterEx function. Otherwise the the message will not be received. It will be blocked by UIPI.

Re: IPC Thru WM_COPYDATA

ForNow4-Feb-17 16:46

ForNow

4-Feb-17 16:46

Thanks for your help I just tried

C++

ChangeWindowMessageFilterEx

I got a FALSE GetLastError returned ERROR_ACCESS_DENIED

This is because my process is at SECURITY_MANDATORY_LOW_RID

AnyWay I can Change this. Thing is I understand the concern for security however I (my process ) created the child process so I should be able and send messages

Re: IPC Thru WM_COPYDATA

Jochen Arndt4-Feb-17 23:37

Jochen Arndt

4-Feb-17 23:37

It's not a problem of sending messages but of receiving. So the only solution would be increasing the UIPI level of your MFC application or using another IPC method.

Re: IPC Thru WM_COPYDATA

ForNow5-Feb-17 3:01

ForNow

5-Feb-17 3:01

Thanks I didn't read it entirely
For a Mainframe in the OnCreate and for a modless dialog I'll put it in the OnInitDialog

Re: IPC Thru WM_COPYDATA

ForNow5-Feb-17 14:19

ForNow

5-Feb-17 14:19

Still works intermittently I am going to try DDE since my code is based on messages

Re: IPC Thru WM_COPYDATA

Rick York9-Feb-17 6:58

Rick York

9-Feb-17 6:58

Many, many years ago I wrote a very simple app to demonstrate the use of WM_COPYDATA with MFC and I see that it is still online : Inter-Process Communication Using WM_COPYDATA[^]

I rebuilt it just now in VS2015 (with very little effort) and it still works on W10. You might want to have a look at it as an example.

Re: IPC Thru WM_COPYDATA

ForNow9-Feb-17 8:22

ForNow

9-Feb-17 8:22

I originally had the WM_COPYDATA as a ON_MESSAGE message map handler than I noticed the OnCopyData I wasn't able to get it to work with that as well

My current method works fine as I don't have to wait for a reply with the SetEvent and shared storage thanks for your help

Re: IPC Thru WM_COPYDATA

leon de boer2-Feb-17 23:45

leon de boer

2-Feb-17 23:45

I am not sure the copydata can be local but for safety I would just use globalalloc anyhow

HGLOBAL hgbl = GlobalAlloc(GMEM_ZEROINIT, sizeof(COPYDATASTRUCT) );  // Allocate the global memory
 COPYDATASTRUCT* cpd = (COPYDATASTRUCT*)GlobalLock(hgbl);        // Lock the allocated memory to a pointer

//..... use an abuse the pointer .. when you are done

GlobalUnlock(hgbl);             // Release lock on the memory block

// Reciever then locks and plays and unlocks

// ......zzzz sometime later one of the two parties

GlobalFree(hgbl);	            // Free the allocated memory

Not sure it's the problem but at least then when know the memory passed is valid to both parts.

In vino veritas

modified 3-Feb-17 6:06am.

Thr problem of the recursive algorithm to do binary search in a sorted array

alalba2-Feb-17 15:37

alalba

2-Feb-17 15:37

I want to inplement a binary search algorithm of an order array.

int Array::Search(int target, int* start, int* tail){
	if(start>tail){
		cout<<"not find"<<endl;
		return -1;
	}
	int offsetMid= (tail-start)/2/sizeof(int);//by unit of int
	cout<<"offset: "<<offsetMid<<"  mid " <<*(start+offsetMid)<<endl;
	cout<<start<<" " <<tail<<endl;
	if(target == *(start+offsetMid) ){
		cout<<"mid"<<endl;
		return (offsetMid+1);
	}
	if(*(start+offsetMid) > target){
		cout<<"left"<<endl;
		tail = start+(offsetMid-1)*sizeof(int);
		return Search(target, start, tail);
	}
	if(*(start+offsetMid) < target){
		cout<<"right"<<endl;
		start = start+(offsetMid)*sizeof(int);
		return Search(target,start , tail);
	}
}

But it doesn't work, I know the parameter of the func should better be the index of the array rather than a pointor, I just want to try this way. The compiler I used is

gcc version 6.2.1 20160916 (Red Hat 6.2.1-2) (GCC)

Another weird thing

int offsetMid= (tail-start)/2/sizeof(int);//by unit of int

Both tail and start are the type of int*, but the difference of them is counted by byte, so I must divide it by sizeof(int) to get the offset value.

if(*(start+offsetMid) > target)

But when I want to plus the offset value to the start address to get the value in a particular position, I shouldn't time it by sizeof(int).WHY??

Re: Thr problem of the recursive algorithm to do binary search in a sorted array

Midi_Mick2-Feb-17 16:12

Midi_Mick

2-Feb-17 16:12

You have already asked this question in QA. Please do not repeat questions in multiple places. Choose your forum, and stick with it.

Cheers,

Mick
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