I have a problem after upgrading Delphi.
I have this code:
function EnumerateWindows(hWnd: HWND; lparam:LPARAM):Bool;
var
ClassName, TheText : Array [0..255] of char;
sName : string;
begin
Application.ProcessMessages;
GetClassNAme(hWnd,Classname, 255);
if GetWindowText(hWnd, TheText, 255) > 0 then
begin
sName := StrPas(TheText);
if pos('NOTEPAD',UpperCase(sName)) > 0 then
postMessage(FindWindow(ClassName, TheText), WM_CLOSE, 0, 0);
end;
procedure TForm1.Button1Click(Sender: TObject);
begin
EnumWindows(#EnumerateWindows,0);
end;
In Delphi 7 the code above is working perfectly anytime there is NOTEPAD title and the program will kill its process but when I tried to use Selphi 10.3 the code above is not working. When i open Notepad it does not kill the process (there is no error in compiler).
Is there any way to make the code work in Delphi 10.3?
i finally managed to fix it...
when i added this
Result := True;
after if condition the code is working.
You have to either use
the types AnsiChar and AnsiString or
the functions GetClassNameW(), GetWindowTextW(), StrPasW() and FindWindowW()
...because Delphi 7 uses by default ANSI and Delphi 10 by default WIDE. You could also use Unicode in Delphi 7 right away by using all the WIDE functions and the types WideChar and WideString. Edit: the previous text is wrong as per Remy's comment.
Furthermore no process is killed: WM_CLOSE merely requests a window to be closed - there is neither a guarantee that the process really closes that window (i.e. for Notepad it can still result in a question dialog if you want to save your edits or not), nor that the process would end after closing that window - processes can run without windows. To kill a process you have to use TerminateProcess().
Related
I have been asked to correct an issue (not related to this question) in a legacy Delphi program. After fixing some issues with missing components, I am now stuck with some GDI Plus functionality, which stops me from compiling the program. One of the functions where this is used is:
function TDownLoadItem.LoadRawBitmapFromStream(var bm: TBitmap): Boolean;
var
image: TGPBitmap;
begin
Result := False;
if Content.Size = 0 then
exit;
// NOTE: Content is a TMemoryStream, declared globally.
image := GDIPlusHelper.LoadBitmapFromStream(Content); // <== This is where the problem is....
try
bm.Width := image.GetWidth;
bm.Height := image.GetHeight;
with TGPGraphics.Create(bm.Canvas.Handle) do
try
DrawImage(image, 0, 0, image.GetWidth, image.GetHeight);
Result := True;
finally
Free;
end;
finally
image.Free;
end;
end;
I think (not sure) the last Delphi version used was 2006, I am on Delphi Rio 10.3.
Online I have managed to find GDI+ 1.2, but this does not solve the problem. The procedure LoadBitmapFromStream does not exit in these libraries. GDIPlusHelper was apparently renamed to GDIPlusHelpers and most code has changed from classes to interfaces. I suspect an older edition of the GDI Plus libraries were used, but I cannot find these.
Reworking the code would be too complex as it would require Content to be an IStream instead of a TMemoryStream. Also, simply using a TBitmap is not feasible either as other code (not shown) uses functionality specific to TGPBitmap (e.g. RotateFlip).
Any suggestions on how to fix/work around this? Thanks in advance!
In many confirmation dialogs it is usefull to have such option (quick wayt to disable confirmation).
But i can't find how to do that. I don't want to design it myself because i need this dialog to be standard-like and don't wont to redesign with every update of Delphi. Is there simple way to use Delphi standard confirmation dialog with such checkbox ?
UPDATE2. Suggested SynTaskDialog library from Synopse project does great job (all i need and even more), i will use it in my projects. Thanks!
UPDATE. So, thank you guys for ideas. System function MessageBoxCheck is nice solution but seem to be not so stable as it should be. In general i agree that it is good idea to use latest API functions to provide users with best UI experience of modern os and use old-fashioned design for older systems. At moment i stay on simple solution (code is following), but if someone share the code with support of UI for modern OS, it will be nice.
function MsgDlgWithCB(const Msg,Title,CBMsg: string; DlgType: TMsgDlgType;
Buttons: TMsgDlgButtons; DefaultButton: TMsgDlgBtn;
var cbDontAskAnymore: TCheckBox): TForm;
var
i: integer;
b: TButton;
y: integer;
begin
Result := CreateMessageDialog(Msg, DlgType, Buttons, DefaultButton) ;
Result.Position := poScreenCenter;
cbDontAskAnymore := TCheckBox.Create(Result);
cbDontAskAnymore.Caption := CBMsg;
cbDontAskAnymore.Width := 130;
y := -1;
for i := 0 to result.ComponentCount-1 do
if result.Components[i] is TButton then
begin
b := TButton(result.Components[i]);
b.Left := b.Left + cbDontAskAnymore.Width + 16;
Result.ClientWidth := Max(Result.ClientWidth, b.Left+b.Width+16);
y := b.Top+b.Height-cbDontAskAnymore.Height;
end;
if y<0 then
y := Result.ClientHeight - cbDontAskAnymore.height - 16;
Result.Caption := Title;
cbDontAskAnymore.Parent := Result;
cbDontAskAnymore.Top := y;
cbDontAskAnymore.Left := 8;
end;
function MessageDlgCheckbox(const Msg: string; DlgType: TMsgDlgType;
Buttons: TMsgDlgButtons; DefaultButton: TMsgDlgBtn;
var cbDontAskAnymore: Boolean;
const Title: string ='Confirmation';
const CBMsg: string = 'Don''t ask anymore'): integer;
var
f: TForm;
c: TCheckbox;
begin
f := MsgDlgWithCB(Msg,Title,CBMsg,DlgType,Buttons,DefaultButton,c);
try
result := f.ShowModal;
cbDontAskAnymore := c.Checked;
finally
f.free;
end;
end;
You can use our Open Source SynTaskDialog unit.
Windows provides a generic task dialog available since Vista/Seven. But there is none available with previous versions of Windows, i.e. Windows XP or 2K.
This unit (licensed under a MPL/GPL/LGPL tri-license) will use the new TaskDialog API under Vista/Seven, and emulate it with pure Delphi code and standard themed VCL components under XP or 2K. It supports Delphi 6 up to XE4, and is Win32/Win64 Unicode ready.
Here is the result under a Windows Seven 64 bit computer:
And here is the same dialog created from our emulated pure Delphi code:
Since this screenshot was made on a Win 7 machine, the styling is native for that OS. When the emulated version of the dialog runs on XP it displays in a style native to that OS.
You have your "Do not ask for this setting next time" checkbox... and potentially much more!
The system native functionality that offers such facilities is the task dialog API introduced in Vista. This provides means for you to show much more capable dialogs than the older MessageBox API.
Should you need to support XP then you will have to create your own dialog. For example by deriving from TForm and calling ShowModal. If you do this, make the form capable of building itself dynamically. Don't make one form per message that you show!
In my codebase, I have my own wrapper of the task dialog API. This detects at runtime versions of Windows that do not support task dialog and falls back on a custom built Delphi dialog.
Regarding SHMessageBoxCheck I'd be a little wary of taking a dependency on that. According to its documentation it's not supported beyond XP, and you have to import it by ordinal. I'd personally be worried that it might be dropped from a future version of Windows. That said, MS has a strong track record of doing whatever it takes to keep legacy apps working with new OS releases.
I need to send several virtual keys (VK_RETURN) from my delphi application (myapp.exe) into another application (target.exe).
Eg : Send VK_RETURN twice , from myapp.exe , into target.exe
The OS that I use are Windows 7 64 bit and Windows XP.
I read : How to send an "ENTER" key press to another application? , Send Ctrl+Key to a 3rd Party Application (did not work for me) and other previous asked question.
But still I'm getting confused.
How to set the focus to the target application ?
How to send the virtual keys to the targeted application ?
Simple example : I want to send VK_RETURN twice into notepad.exe or calc.exe (already loaded) or any other program from my delphi application. How to do that ?
The simplest way to do this in Delphi 2010, please...
PS :
I tried SndKey32.pass from http://delphi.about.com/od/adptips2004/a/bltip1104_3.htm
And got error : [DCC Error] SndKey32.pas(420): E2010 Incompatible types: 'Char' and 'AnsiChar'
If (Length(KeyString)=1) then MKey:=vkKeyScan(KeyString[1])
If your target application isn't the foreground window, you need to use PostMessage to send keystrokes to its window handle. You can get that window handle using FindWindow. The code below sends the Enter key to a the text area in a running instance of Notepad (note it uses an additional FindWindowEx to locate the memo area first). It was tested using both Delphi 2007 and Delphi XE4 (32-bit target) on Windows 7 64.
uses Windows;
procedure TForm1.Button1Click(Sender: TObject);
var
NpWnd, NpEdit: HWnd;
begin
NpWnd := FindWindow('Notepad', nil);
if NpWnd <> 0 then
begin
NpEdit := FindWindowEx(NpWnd, 0, 'Edit', nil);
if NpEdit <> 0 then
begin
PostMessage(NpEdit, WM_KEYDOWN, VK_RETURN, 0);
PostMessage(NpEdit, WM_KEYUP, VK_RETURN, 0);
end;
end;
end;
To find the window by title (caption) instead, you can just use the second parameter to FindWindow. This finds a new instance of Notepad with the default 'Untitled' file open:
NpWnd := FindWindow(nil, 'Untitled - Notepad');
Note that this requires as exact match on the window title. An extra space before or after the -, for instance, will cause the match to fail and the window handle to not be retrieved.
You can use both the window class and title if you have multiple instances running. To find the copy of Notepad running with Readme.txt loaded, you would use
NpWnd := FindWindow('Notepad', 'Readme.txt - Notepad');
To find other applications, you'll need to use something like WinSpy or WinSight to find the window class names. (There are others also, such as Winspector or WinDowse (both of which are written in Delphi).)
Your comment mentions Calculator; according to Winspector, the Calculator main window is in a window class called CalcFrame on Windows 7, and the area the numbers are displayed in is a Static window (meaning it doesn't seem to receive keystrokes directly). The buttons are simply called Button, so you'd have to loop through them using EnumChildWindows looking for the individual buttons to identify them in order to obtain their handles.
(How to enumerate child windows is a separate question; you can probably find an example by searching here or via Google. If you can't, post a new, separate question about that and we can try to get you an answer.)
Here's a quick example of sending keys to Calculator after finding it by window class. It doesn't do anything useful, because it needs some time spent to identify different buttons and the keys that each responds to (and the proper combination of messages). This code simply sends 11Numpad+22 to the calculator window (a quick test showed that they were properly received and displayed, and that's about all the time I wanted to spend on the process).
uses Windows;
procedure TForm1.Button1Click(Sender: TObject);
var
NpWnd: HWnd;
begin
NpWnd := FindWindow('CalcFrame', nil);
if NpWnd <> 0 then
begin
PostMessage(NpWnd, WM_KEYDOWN, VK_NUMPAD1, 0);
PostMessage(NpWnd, WM_KEYDOWN, VK_ADD, 0);
PostMessage(NpWnd, WM_KEYDOWN, VK_NUMPAD2, 0);
end;
end;
I've got a Delphi 7.0 application that throws a memory access exception / message box every time it writeln's an empty string from the string list associated with a combo box:
csvstrlst := combobox1.Items;
csvstrlst.clear;
csvstrlst.add(''); //problem
csvstrlst.add('a'); //no problem
csvstrlst.add(''); //problem
csvstrlst.add('b'); //no problem
//throws memory access messages (I think the writeln writes a line though)
for n := 1 to csvstrlst.Count do begin
writeln(out_file,csvstrlst.strings[n-1])
end;
//throws memory access messages (writeln does write a comma text string though)
writeln(out_file,csvstrlst.commatext);
Running on Windows 7 or XP. As application or in D7 IDE. Combobox with empty string items also causes the same error if the parent of the form it is on is changed.
Has anyone else ever seen or heard of this problem? Any other information available at all?
This is a known and solved bug described in QC:
TCombobox gives AV when selecting empty item from dropdown
Although this is a bug, you should not reuse parts from controls to perform some data tasks as described in your question.
You will not save anything doing so, but getting most the time unwanted sideeffects (controls get repainted and/or fire events)
If you want to have a TStringList then create an instance.
csvstrlst := TStringList.Create;
try
// csvstrlst.Clear;
csvstrlst.Add( '' );
csvstrlst.Add( 'a' );
csvstrlst.Add( '' );
csvstrlst.Add( 'b' );
for n := 0 to csvstrlst.Count - 1 do
begin
WriteLn( out_file, csvstrlst[n] )
end;
WriteLn( out_file, csvstrlst.CommaText );
finally
csvstrlst.Free;
end;
As Sir Rufo has discovered the issue is a VCL bug introduced in Delphi 7 as described in QC#2246. According to that report the bug is resolved in a build with major version number 7 so you may be able to fix the problem by applying the latest Delphi 7 updates.
If not then you can fix the problem from the outside. I don't actually have a Delphi 7 installation to test this on, but I believe that this interposer class will work.
type
TFixedComboBoxStrings = class(TComboBoxStrings)
protected
function Get(Index: Integer): string; override;
end;
TComboBox = class(StdCtrls.TComboBox)
protected
function GetItemsClass: TCustomComboBoxStringsClass; override;
end;
function TFixedComboBoxStrings.Get(Index: Integer): string;
var
Len: Integer;
begin
Len := SendMessage(ComboBox.Handle, CB_GETLBTEXTLEN, Index, 0);
if (Len <> CB_ERR) and (Len > 0) then
begin
SetLength(Result, Len);
SendMessage(ComboBox.Handle, CB_GETLBTEXT, Index, Longint(PChar(Result)));
end
else
SetLength(Result, 0);
end;
function TComboBox.GetItemsClass: TCustomComboBoxStringsClass;
begin
Result := TFixedComboBoxStrings;
end;
The bug that was introduced in Delphi 7 is simply that the if statement reads:
if Len <> CB_ERR then
So, when Len is zero, that is when the item is the empty string, the True branch of the if is chosen. Then, the SendMessage becomes:
SendMessage(ComboBox.Handle, CB_GETLBTEXT, Index, Longint(PChar('')));
Now, PChar('') has special treatment and evaluates to a pointer to read only memory containing a zero character. And so when the combo box window procedure attempts to write to that memory, an access violation occurs because the memory is read only.
Delphi 2010 has a nice set of new file access functions in IOUtils.pas (I especially like the UTC versions of the date-related functions). What I miss so far is something like
TFile.GetSize (const Path : String)
What is the Delphi 2010-way to get the size of a file? Do I have to go back and use FindFirst to access TSearchRec.FindData?
Thanks.
I'm not sure if there's a "Delphi 2010" way, but there is a Windows way that doesn't involve FindFirst and all that jazz.
I threw together this Delphi conversion of that routine (and in the process modified it to handle > 4GB size files, should you need that).
uses
WinApi.Windows;
function FileSize(const aFilename: String): Int64;
var
info: TWin32FileAttributeData;
begin
result := -1;
if NOT GetFileAttributesEx(PChar(aFileName), GetFileExInfoStandard, #info) then
EXIT;
result := Int64(info.nFileSizeLow) or Int64(info.nFileSizeHigh shl 32);
end;
You could actually just use GetFileSize() but this requires a file HANDLE, not just a file name, and similar to the GetCompressedFileSize() suggestion, this requires two variables to call. Both GetFileSize() and GetCompressedFileSize() overload their return value, so testing for success and ensuring a valid result is just that little bit more awkward.
GetFileSizeEx() avoids the nitty gritty of handling > 4GB file sizes and detecting valid results, but also requires a file HANDLE, rather than a name, and (as of Delphi 2009 at least, I haven't checked 2010) isn't declared for you in the VCL anywhere, you would have to provide your own import declaration.
Using an Indy unit:
uses IdGlobalProtocols;
function FileSizeByName(const AFilename: TIdFileName): Int64;
You can also use DSiFileSize from DSiWin32. Works in "all" Delphis. Internally it calls CreateFile and GetFileSize.
function DSiFileSize(const fileName: string): int64;
var
fHandle: DWORD;
begin
fHandle := CreateFile(PChar(fileName), 0, 0, nil, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0);
if fHandle = INVALID_HANDLE_VALUE then
Result := -1
else try
Int64Rec(Result).Lo := GetFileSize(fHandle, #Int64Rec(Result).Hi);
finally CloseHandle(fHandle); end;
end; { DSiFileSize }
I'd like to mention few Pure Delphi ways. Though i think Deltics made a most speed-effective answer for Windows platform, yet sometimes you want just rely on RTL and also make portable code that would work in Delphi for MacOS or in FreePascal/Virtual Pascal/whatever.
There is FileSize function left from Turbo Pascal days.
http://turbopascal.org/system-functions-filepos-and-filesize
http://docwiki.embarcadero.com/CodeExamples/XE2/en/SystemFileSize_(Delphi)
http://docwiki.embarcadero.com/Libraries/XE2/en/System.FileSize
The sample above lacks "read-only" mode setting. You would require that to open r/o file such as one on CD-ROM media or in folder with ACLs set to r/o. Before calling ReSet there should be zero assigned to FileMode global var.
http://docwiki.embarcadero.com/Libraries/XE2/en/System.FileMode
It would not work on files above 2GB size (maybe with negative to cardinal cast - up to 4GB) but is "out of the box" one.
There is one more approach, that you may be familiar if you ever did ASM programming for MS-DOS. You Seek file pointer to 1st byte, then to last byte, and check the difference.
I can't say exactly which Delphi version introduced those, but i think it was already in some ancient version like D5 or D7, though that is just common sense and i cannot check it.
That would take you an extra THandle variable and try-finally block to always close the handle after size was obtained.
Sample of getting length and such
http://docwiki.embarcadero.com/Libraries/XE2/en/System.SysUtils.FileOpen
http://docwiki.embarcadero.com/Libraries/XE2/en/System.SysUtils.FileSeek
Aside from 1st approach this is int64-capable.
It is also compatible with FreePascal, though with some limitations
http://www.freepascal.org/docs-html/rtl/sysutils/fileopen.html
You can also create and use TFileStream-typed object - which was the primary, officially blessed avenue for file operations since Delphi 1.0
http://www.freepascal.org/docs-html/rtl/classes/tfilestream.create.html
http://www.freepascal.org/docs-html/rtl/classes/tstream.size.html
http://docwiki.embarcadero.com/Libraries/XE2/en/System.Classes.TFileStream.Create
http://docwiki.embarcadero.com/Libraries/XE2/en/System.Classes.TStream.Size
As a side note, this avenue is of course integrated with aforementioned IOUtils unit.
http://docwiki.embarcadero.com/Libraries/XE3/en/System.IOUtils.TFile.OpenRead
This is a short solution using FileSize that does the job:
function GetFileSize(p_sFilePath : string) : Int64;
var
oFile : file of Byte;
begin
Result := -1;
AssignFile(oFile, p_sFilePath);
try
Reset(oFile);
Result := FileSize(oFile);
finally
CloseFile(oFile);
end;
end;
From what I know, FileSize is available only from XE2.
uses
System.Classes, System.IOUtils;
function GetFileSize(const FileName : string) : Int64;
var
Reader: TFileStream;
begin
Reader := TFile.OpenRead(FileName);
try
result := Reader.Size;
finally
Reader.Free;
end;
end;