C / C++ / MFC

21-Sep-06 6:31

I have written a C++ program and I wish it to be able to be started by dragging a file icon onto the program icon in windows explorer. The program name is prog.exe, the file name is file.syx, they are both in folder "H:\folder". When the file is dragged onto the program icon in explorer and starts, the value of _argc=1 with _argv[0] being "H:\folder\prog.exe" and _argv[1] being "H:\folder\file.syx" as expected. I then use this information to open file.syx.

However, if the program and file are moved to a folder with a space in the name such as "H:\copy of folder", then when I drag file.syx onto prog.exe I get these unexpected results. _argc=3 with _argv[0]="H:\folder\prog.exe", _argv[1]="of", _argv[2] = "folder\prog.exe H:\copyof~2\file.syx".

If I just double click "H:\copy of folder\prog.exe" I get _argc=3 with _argv[0]="H:\folder\prog.exe", _argv[1]="of", _argv[2] = "folder\prog.exe ".

I have tested this program on windows98 and windowsXP with the same basic results. If anybody knows how to consistently get the name of a file that is ‘dragged onto a program icon to start that program’ from inside that program then I would appreciate the help.

David Crow21-Sep-06 6:49

21-Sep-06 6:49

If this is a Windows application, why aren't you using the standard drag&drop interface instead of argc/argv?

"Talent without discipline is like an octopus on roller skates. There's plenty of movement, but you never know if it's going to be forward, backwards, or sideways." - H. Jackson Brown, Jr.

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

hlmechanic21-Sep-06 6:56

21-Sep-06 6:56

this program also has drag&drop where a person could drag a file onto the open window of the program to open that file. I wish to be able to open the file as the program starts up. I beleve this would also let me set the file extenshion (.syx) to that double clicking a .syx file would open that file in this program.

David Crow21-Sep-06 7:00

21-Sep-06 7:00

If double-clicking a .syx file is not working, then you need to adjust its registry setting by surrounding the %1 parameter in double quotes.

hlmechanic21-Sep-06 7:12

21-Sep-06 7:12

I have went to folder options and set .syx to open H:\copy of folder\prog.exe Now when I double click a .syx file , it opens prog.exe but I do not know how to get the information about the opening file other than to us _argv, and it gives strange results. I beleive I am missing somethin since standard programs such as notepade and others do this with no apparent problem.

David Crow21-Sep-06 7:26

21-Sep-06 7:26

Do you have a console or a Windows application?

Look in the registry for your .syx extension and note what you see. How is %1 being handled?

hlmechanic21-Sep-06 7:35

21-Sep-06 7:35

I am curently using windows98. I have open regedit and did a search for .syx and did not find anything with %1 in it. I am afraid you may be going over my head. i.e. i'm lost.

David Crow21-Sep-06 7:42

21-Sep-06 7:42

hlmechanic wrote:
I am curently using windows98.

Which matters not.

hlmechanic wrote:
I have open regedit and did a search for .syx

It should be near the top of the HKEY_CLASSES_ROOT hive with all of the other file extension types.

For example, if you look for .txt, you'll see it has a default value of txtfile. Looking further down the list for txtfile, you should find:

HKEY_CLASSES_ROOT\txtfile\shell\open\command

Does the same sort of thing not exist for your .syx extension?

hlmechanic21-Sep-06 8:05

21-Sep-06 8:05

under HKEY_CLASSES_ROOT/.syx It says (default) "syx_auto_file"
under HKEY_CLASSES_ROOT/syx_auto_file it says (default) SYX File
SYX File does not show up anywhere else

David Crow21-Sep-06 8:47

21-Sep-06 8:47

hlmechanic wrote:
under HKEY_CLASSES_ROOT/syx_auto_file it says (default) SYX File

You should have a shell key under that. In all, it should look like:

HKEY_CLASSES_ROOT\syx_auto_file\shell\open\command

If not, why not make the necessary changes to see if that helps.

hlmechanic21-Sep-06 8:57

21-Sep-06 8:57

I must have missed the + befor the folder icon becouse there is HKEY_CLASSES_ROOT\syx_auto_file\shell\open\command and it's value is ""H:\Copy of folder\prog.exe"%1"

My apoligies for missing this the first time.

David Crow21-Sep-06 9:15

21-Sep-06 9:15

This is just a guess, but those double quotes look ill-placed. It's hard to tell which are actually part of the registry's value and which you added as part of the post. I would have thought it to look something like:

"H:\Copy of folder\prog.exe" "%1"

hlmechanic21-Sep-06 9:55

21-Sep-06 9:55

I got it to look like you said. now when I double click a .syx file I get _argc=4 with _argv[3] as H:\copyof~2\file.syx

I could use _argv[_argc-1] to get this value but I still get unexpected results from just double clicking the aplication icon in explorer window.

p.s. what does the %1 do?

David Crow21-Sep-06 10:09

21-Sep-06 10:09

hlmechanic wrote:
now when I double click a .syx file I get _argc=4...

Which it should be 2.

hlmechanic wrote:
with _argv[3] as H:\copyof~2\file.syx

What is the value of _argv[0], _argv[1], and _argv[2]?

hlmechanic wrote:
p.s. what does the %1 do?

Nothing per se. It gets replaced by the file that was double-clicked.

"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15

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

hlmechanic21-Sep-06 12:09

21-Sep-06 12:09

I am no longer at the same computer. now I am at a computer running windows XP. It gives me _argc=5. _argv[0] is still what is expected. The rest seem to be "H:\Copy of folder\prog.exe H:\Copy of folder\file.syx" with each _argv[] after 0 being a part of the line between spaces (except the space between the two file names). Windows seems to be trying to break the line up into arguments as a dos line would be. I was wishing there was a way to get this information that did not involve _argv[] or some way to make it give me the whole line so that I could break it up as I wanted.

Also I wanted to thank you for your help.

David Crow22-Sep-06 3:02

22-Sep-06 3:02

You still have not indicated whether this is a console or GUI application. That makes a ton of difference in how command-line arguments and drag/drop operations are handled.

"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15

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

hlmechanic21-Sep-06 17:01

21-Sep-06 17:01

I have found GetCommandLine() wich seems to be promising. When H:\copy of folder\file.syx is draged and droped onto H:\copy of folder\prog.exe then GetCommndLine() returns "H:\copy of folder\prog.exe" ":\copy of folder\file.syx" (including quote marks). If the same thing is done in H:\folder then "H:\copy of folder\prog.exe" H:\copy of folder\file.syx is given (note change in quote marks). I think I can get the filename from this.

I found this from the questions and answers at the end of the folowing article
Managing argc and argv[] with STL in a simple way

specal thanks to DavidCrow for trying to educate me.

David Crow22-Sep-06 3:16

22-Sep-06 3:16

If this is a GUI application, are you handling the WM_DROPFILES message?

"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15

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

hlmechanic22-Sep-06 4:06

22-Sep-06 4:06

This is a GUI. Written in Borland C++ 4.52
I handled WM_DROPFILES with the folowing code.

void DrumWindow::EvDropFiles(TDropInfo dropInfo){
int NumFiles;
char NextFile [MAX_PATH];
NumFiles = dropInfo.DragQueryFile (-1, NULL, 0 );// Get the # of files being dropped.;
for (int File = 0; File < NumFiles; File++ ){
if ( dropInfo.DragQueryFile (File,NextFile,MAX_PATH ) > 0 ){// Get the next filename from the HDROP info.

/////work with file name NextFile here if valid (removed to keep short)

};//end if next exist
};//end for each file
dropInfo.DragFinish ();// Free up memory.
};//end EvDropfiles

David Crow22-Sep-06 5:21

22-Sep-06 5:21

I'm confused. Why are you using GetCommandLine() when DragQueryFile() is how "dropped" files are retrieved?

"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15

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

hlmechanic22-Sep-06 5:42

win32 API - How to use a button

22-Sep-06 5:42

my wish is to find out wich file was used to start the program by dragging the icon of the file onto the unopened program icon. I would also like to be able to set the file extenshion to open the file using this program so the user can double click on a file with the right extenshion and start the program with that file loaded into it. I do not know how to make DragQueryFile() tell me wich file was used to start the program.

The Drag and Drop onto the open program window works great but I have not noticed that it sends any information about a file that was draged onto the unopened program icon in windows explorer, or about wich program was double clicked to start this program. I suspect that this is because DragAcceptFiles is not called untill 'SetupWindow()'

IF there is a better place to put DragAcceptFiles that would let the program find out this information it would be much easyer to do.

gunner_uk200021-Sep-06 6:13

gunner_uk2000

21-Sep-06 6:13

I have used the following tutorials to get a window on the screen.

http://www.zeuscmd.com/tutorials/win32/05-CreatingWindows.php

This is fine as the person writing it give pretty good explainations of what he does.

I have been unable to fine out how to put a button onto this screen as i cannot find and decent guides for this. Microsofts documentation is quite horrid, poorly orgainized and spits huge reams of code at you with little in the way of commenting.

Look at the java documentation for how it should be done tbh.

Now that mini rant is over this is my code that i copied from MSDN for putting a button on the screen.

<br />
	hwndButton = CreateWindow( <br />
    "BUTTON",   // predefined class <br />
    "Do Something",       // button text <br />
    WS_VISIBLE | WS_CHILD | BS_DEFPUSHBUTTON,  // styles <br />
 <br />
    // Size and position values are given explicitly, because <br />
    // the CW_USEDEFAULT constant gives zero values for buttons. <br />
    10,         // starting x position <br />
    10,         // starting y position <br />
    130,        // button width <br />
    20,        // button height <br />
    hwnd,       // parent window <br />
    NULL,       // No menu <br />
    (HINSTANCE) GetWindowLong(hwnd, GWL_HINSTANCE), <br />
    NULL);      // pointer not needed <br />

It does just that and its is one of the better commented examples and i have put two buttons on the screen.

What i cannot work out is how to identify the buttons when the message handles method is called.

this is coded as follows:

LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)<br />
{<br />
	switch(msg)<br />
	{<br />
	case WM_CLOSE :<br />
		DestroyWindow(hwnd);<br />
		break;<br />
<br />
	case WM_DESTROY :<br />
		PostQuitMessage(0);<br />
		break;<br />
	case WM_KEYDOWN:<br />
		if(wParam == 'U'){<br />
			MessageBox(NULL, "U Pressed", "U", MB_OK);<br />
		}<br />
		break;<br />
	case WM_KEYUP:<br />
		if(wParam == 'L'){<br />
			MessageBox(NULL, "L Released", "L", MB_OK);<br />
		}<br />
	<br />
	case BN_CLICKED:<br />
		if(true) //have no idea what to put in here to work out which button was press.<br />
			MessageBox(NULL, "left ", "L", MB_OK);<br />
		else<br />
			MessageBox(NULL, "right ", "L", MB_OK);<br />
	}<br />
	return DefWindowProc(hwnd, msg, wParam, lParam);<br />
}

Anyone have any ideas? or any links to decent guides to win32 programming? (which don't just tell you have to get visual studio to generate the code for you)

Re: win32 API - How to use a button

David Crow21-Sep-06 6:56