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Re: Read a file on click event

CodingLover16-Oct-07 19:11

CodingLover

16-Oct-07 19:11

Thanks, seems now I'm getting better and better with all of your guys suggestions. Wink | ;)

But the following part is not clear, when I do it it wont print any value to the file. Just print an annoying character.

Mark Salsbery wrote:
openFile.Write(&len, sizeof(UINT)); // write the string length (in TCHARs)

I appreciate your help all the time...
Eranga Smile | :)

Re: Read a file on click event

chandu00416-Oct-07 20:58

chandu004

16-Oct-07 20:58

come on eranga, all this is confusing because, the thread length has got very big.
i think, you have got some clues right, so you must have solved some of your problems and got some more.
so create a new thread, and state that, with reference to the this thread, and specify your new problems.
we shall help you with fresh mind.
gud luck.
and btw, you didnt reply weather u got your solution, with my earlier suggestion. i.e. CFile returns the size of the file.

Re: Read a file on click event

CodingLover16-Oct-07 21:08

CodingLover

16-Oct-07 21:08

Ya, this is going to be a long thread. I've do this up to now. Find the number bytes and use it to read the file as follows.

<br />
void CSRFToolDlg::OnBnClickedWrite()<br />
{<br />
	GetDlgItemText(IDC_S_WRITE, readString) ;<br />
    UINT len = readString.GetLength() ;<br />
    openFile.Write(&len, sizeof(UINT)) ; <br />
    if (len > 0)<br />
	{<br />
        openFile.Write((LPVOID)(LPCTSTR)readString, len * sizeof(TCHAR)) ;<br />
	}<br />
    AfxMessageBox("Data write to the file successfully", MB_OK) ;<br />
}<br />
<br />
<br />
void CSRFToolDlg::OnBnClickedRead()<br />
{<br />
	TCHAR tempBuffer[256];<br />
    UINT len;<br />
<br />
    openFile.SeekToBegin();<br />
<br />
    openFile.Read(&len, sizeof(UINT));    <br />
<br />
    if (len > 0)<br />
    {<br />
        openFile.Read(tempBuffer, len * sizeof(TCHAR)) ;<br />
        tempBuffer[len] = _T('\0');<br />
    }<br />
    else<br />
    {<br />
        tempBuffer[0] = _T('\0');<br />
    }<br />
<br />
    SetDlgItemText(IDC_S_READ, tempBuffer) ;<br />
}<br />

Here the issue is, the length of the string is nor write properly to the file. You have my full code, try those two functions there. you will see what I'm saying.

After solving this I'll start a new one for next cases.

I appreciate your help all the time...
Eranga Smile | :)

Re: Read a file on click event

Mark Salsbery17-Oct-07 5:21

Mark Salsbery

17-Oct-07 5:21

Eranga Thennakoon wrote:
But the following part is not clear, when I do it it wont print any value to the file. Just print an annoying character.

You missed my point entirely.

You need some way to determine how long the string is.
You can't just call strlen() on an uninitialized char array.

If the string is the entire file use chandu004's suggestion -
you can read it all in one shot.

Otherwise, you're going to need to learn about "strings"
(char arrays), files, etc. before you'll understand any of this.

I gave one example that writes the string length so you know how much
to read later. Your CFile is in binary mode - I wrote binary data.
The "annoying character" was never meant to be a readable character.

If everything in the file needs to be text, you need to deal with that.
Whether you use endlines, carriage-return/linefeeed pairs, or some other
escape character to separate your strings is up to you.

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

How to access all the Editboxes in a form.

Anand Todkar15-Oct-07 19:12

Anand Todkar

15-Oct-07 19:12

I have more than 50 Edit boexs in a form and I want to access them in a loop rather than accessing one by one, Is there any way by which I can do it?

Thanks,
Anand.

Re: How to access all the Editboxes in a form.

Hamid_RT15-Oct-07 19:19

Hamid_RT

15-Oct-07 19:19

Each editbox has an ID if you set these ids for example of 100 to 150 on the resource.h you can use of a loop.

Re: How to access all the Editboxes in a form.

Anand Todkar15-Oct-07 19:24

Anand Todkar

15-Oct-07 19:24

Yeah right, but the project has more than 50 forms and i have to do this for all forms, already the resource IDs are tightly bound ... more , it is not reliable to .. So i was thinking if some generic loop by which we can access all the controls on form and then screen out the other controls.

Thanks,
Anand.

Re: How to access all the Editboxes in a form.

Naveen15-Oct-07 19:28

Naveen

15-Oct-07 19:28

Anand Todkar wrote:
Yeah right, but the project has more than 50 forms

Do all the forms have a common main dialog?

nave

[OpenedFileFinder]

Re: How to access all the Editboxes in a form.

David Crow16-Oct-07 2:23

David Crow

16-Oct-07 2:23

Anand Todkar wrote:
...already the resource IDs are tightly bound ... more , it is not reliable to...

What exactly do you mean by this? Why can't you just open the project's resource.h file (or whatever you have named it) and renumber the controls such that they are sequential?

"A good athlete is the result of a good and worthy opponent." - David Crow

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

Re: How to access all the Editboxes in a form.

Anand Todkar16-Oct-07 2:34

Anand Todkar

16-Oct-07 2:34

Yeah David, you are right, i done the changes in Resource file and accessed the Controls in a loop.

Thanks for your help.

Thanks,
Anand.

Re: How to access all the Editboxes in a form.

CodingLover15-Oct-07 19:26

CodingLover

15-Oct-07 19:26

You mean something like that,

#define IDC_ONE 1000<br />
#define IDC_TWO 1001

So, there can I use any number. I mean there is no restrictions on predefined events?

I appreciate your help all the time...
Eranga Smile | :)

Re: How to access all the Editboxes in a form.

Hamid_RT15-Oct-07 19:38

Hamid_RT

15-Oct-07 19:38

Not any number,numbers must unique.

Re: How to access all the Editboxes in a form.

CodingLover15-Oct-07 19:47

CodingLover

15-Oct-07 19:47

Ya, its' true. What I mean that there is any numbers couldn't I use, may be those numbers are already use somewhere in the application.

I appreciate your help all the time...
Eranga Smile | :)

Re: How to access all the Editboxes in a form.

Naveen15-Oct-07 19:25

Naveen

15-Oct-07 19:25

Anand Todkar wrote:
Is there any way by which I can do it?

Set the taborder of all EditBox in a sequence. Now take the handle of EditBox in the top of zorder and call the GetWindow() with GW_HWNDNEXT. This will return the handle to the 2nd EditBox. now pass the 2nd EditBox handle to get third list and so on.

Another option is to set the id value of the EditBox in a sequence. Now call the GetDlgItem() function in a for loop with the index starting from the id of first EditBox to the last one.

nave

[OpenedFileFinder]

Re: How to access all the Editboxes in a form.

Anand Todkar15-Oct-07 19:31

Anand Todkar

15-Oct-07 19:31

Naveen.R wrote:
Set the taborder of all EditBox in a sequence. Now take the handle of EditBox in the top of zorder and call the GetWindow() with GW_HWNDNEXT. This will return the handle to the 2nd EditBox. now pass the 2nd EditBox handle to get third list and so on.

This sounds good, let me try this way, as the Taborder is not going to change.

Thanks naveen Smile | :)

Thanks,
Anand.

Re: How to access all the Editboxes in a form.

Nelek15-Oct-07 21:03

Nelek

15-Oct-07 21:03

Hi,

I made it very easy with an Array from pointers to the control. In my case, it was:

CMyColorComboBox* m_aComboBoxes [MAX];

then, in the constructor of the Dialog... I wrote the access to them.

m_aComboBoxes[0] = &m_cmcbbVisIn1;
m_aComboBoxes[1] = &m_cmcbbVisIn2;
m_aComboBoxes[2] = &m_cmcbbVisIn3;
m_aComboBoxes[3] = &m_cmcbbVisIn4;

and then I use loops to access, write, delete data from them.

for (int i = 0; i < MAX; i++)
   m_aComboBoxes [MAX]->ResetContent ();

I have done it in that way because I had the member variables from class wizard. But you can use the idea as well without having any variable and using GetDlgItem (ID). If you use the GetDlgItem ... then you must use OnInitDialog or on InitialUpdate. Because if you use the constructor to give the pointers... then you will have an assertion because the window doesn't exist when trying to access.

Hope it helps

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

Wink | ;)

List iteration Problem [modified]

ashishbhatt15-Oct-07 19:04

ashishbhatt

15-Oct-07 19:04

Hi All,

I am using list class in my project(MFC Application). I have made list like .....

typedef std::list<rect> rectlist; // Here list is of type RECT

in one header file. And during my project execution I am storing rectangles in the list.

And now,When I use list iterator in another class like below....( I have already included its header file in using class)

rectlist::iterator i;

And i use this iterator like below in any other function......

for (i = rects.begin(); i != rects.end(); i++)
{
CaptureScreen(*i, m_mainbuff); // Error is here
}

I got error msg like ...

list iterator not dereferencable

at runtime in debug assertion Failed Box.

Thanks in Advance...

Ashish

-- modified at 1:10 Tuesday 16th October, 2007

Re: List iteration Problem

zakkas248315-Oct-07 20:11

zakkas2483

15-Oct-07 20:11

it may because of using *i in argument.

solution is try to give appropriate argument in function calling then copy it in to original list.

or it may required type casting..

give me the prototype of CartureScreen( ) function.

Re: List iteration Problem

ashishbhatt15-Oct-07 20:29

ashishbhatt

15-Oct-07 20:29

Prototype of CaptureScreen()...

void CaptureScreen(RECT &UpdateArea, BYTE *scrBuff);

i have just used this ....

<br />
rectlist::iterator i;<br />
<br />
for (i = rects.begin(); i != rects.end(); i++)<br />
{<br />
      CaptureScreen(*i, m_mainbuff);<br />
}<br />
<br />

But in my case it does not go into loop even if condition is true. And if I make..

i == rects.end()

then it goes into the loop but their values are different.And if it goes into loop then it gives error as I explained above.And if I make it like....

<br />
      CaptureScreen((RECT &)i, m_mainbuff);<br />
<br />

then it does not give error.But when for is incremented then again it gives error like....

list iterator is not incremental

That's all the case....

Thanks Hiru.

Re: List iteration Problem

Nelek15-Oct-07 21:05

Nelek

15-Oct-07 21:05

what about with...

rectlist::iterator i;

for (i = rects.begin(); i != rects.end(); i++)
{
CaptureScreen(&i, m_mainbuff);
}

Re: List iteration Problem

zakkas248315-Oct-07 21:38

zakkas2483

15-Oct-07 21:38

Yes, i also think this is true ans..

hiru

Re: List iteration Problem

ashishbhatt15-Oct-07 22:06

ashishbhatt

15-Oct-07 22:06

I have little much found that I am not getting perfect list which I have stored.

here I am fetch the rectangles list from below....

<br />
// Get list of rectangles for checking<br />
	rectlist rectsToScan;<br />
	m_region.Rectangles(rectsToScan);<br />
<br />

m_region is the object of the RTMPRegion class in which i storing rectangles in to the list.

But when I fetch by above then I Test like below.....

<br />
<br />
        rectlist ::iterator i;<br />
	for(i = rectsToScan.begin();i==rectsToScan.end();i++)<br />
		CaptureScreen(*i, m_mainbuff);<br />

Then in the value of i any junk value comes.Here i is RECT ,so in left,right,top,bottom values are junk values.

Re: List iteration Problem

ashishbhatt15-Oct-07 22:17

ashishbhatt

15-Oct-07 22:17

It gives me the error using ....

CaptureScreen(&i, m_mainbuff);

Error like...

error C2664: 'RTMPDesk::CaptureScreen' : cannot convert parameter 1 from 'std::list<_Ty>::_Iterator<_Secure_validation> *__w64 ' to 'RECT &'

My Function deff...

void CaptureScreen(RECT &UpdateArea, BYTE *scrBuff);

thanks.

Re: List iteration Problem

zakkas248315-Oct-07 22:59

zakkas2483

15-Oct-07 22:59

Try this
CaptureScreen( i ,m_mainbuff );

Re: List iteration Problem

ashishbhatt15-Oct-07 23:16

ashishbhatt

15-Oct-07 23:16

Thanks Hiru,,

Just before your message comes I found little solution and that is like that I did not get exect values from the list thats why it gave me error.At right now I am not getting error.

I am using same as

CaptureScreen(*i,m_Mainbuff);

If there will be some problem then i will contact U.

Thanks for your valuable time.Thank u v much.

Ashu

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