program CNCGIS;uses Forms, Controls, ......{$R *.RES} var HMuTex:HWnd; Ret:Integer;begin //使程序只运行一次 Added by HGB HMuTex:=CreateMuTex(nil,false,'Mutex_JSTRD_Application'); Ret:=GetLastError; if Ret <> Error_Already_Exists then begin Application.Initialize; Application.CreateForm(TForm1, Form1); ..... Application.Run; end else begin ReleaseMuTex(HMuTex); MessageBox(0,'程序已经启动!','提示信息',MB_ICONINFORMATION); end; end.
改写.dpr文件: var aHandle: THandle;{$R *.res}begin Application.Initialize; aHandle := FindWindow(nil, '我的程序'); if aHandle <> 0 then begin if IsIconic(aHandle) then SendMessage(aHandle, WM_SYSCOMMAND, SC_RESTORE, 0); SetForeGroundWindow(aHandle); Application.Terminate; Exit; end; Application.Title := '我的程序'; Application.CreateForm(TfrmSec, frmSec); Application.Run; end.
procedure TFrm_Main.SpeedButton1Click(Sender: TObject); var HWndCalculator : HWnd; begin HWndCalculator := FindWindow(nil, 'P_PublicHouse'); if HWndCalculator<>0 then begin application.message('此程序已经启动'); exit; end; end;
只需3行代码: CreateMutex(nil,true,'我的程序'); if GetLastError = ERROR_ALREADY_EXISTS then Application.Terminate; 将这段程序加在程序的FormCreate中就可以了!
delphi的socketserver列子 CreateMutex(nil, True, 'SCKTSRVR'); if GetLastError = ERROR_ALREADY_EXISTS then begin MessageBox(0, PChar(SAlreadyRunning), SApplicationName, MB_ICONERROR); Halt; end;
uses这个单元即可unit RunOne;interfaceconst MI_QUERYWINDOWHANDLE = 1; MI_RESPONDWINDOWHANDLE = 2; MI_ERROR_NONE = 0; MI_ERROR_FAILSUBCLASS = 1; MI_ERROR_CREATINGMUTEX = 2;// Call this function to determine if error occurred in startup. // Value will be one or more of the MI_ERROR_* error flags. function GetMIError: Integer;implementationuses Forms, Windows, SysUtils;const UniqueAppStr = 'ShuanYuan_SoftWare';var MessageId: Integer; WProc: TFNWndProc; MutHandle: THandle; MIError: Integer;function GetMIError: Integer; begin Result := MIError; end;function NewWndProc(Handle: HWND; Msg: Integer; wParam, lParam: Longint): Longint; stdcall; begin Result := 0; // If this is the registered message... if Msg = MessageID then begin case wParam of MI_QUERYWINDOWHANDLE: // A new instance is asking for main window handle in order // to focus the main window, so normalize app and send back // message with main window handle. begin if IsIconic(Application.Handle) then begin Application.MainForm.WindowState := wsNormal; Application.Restore; end; PostMessage(HWND(lParam), MessageID, MI_RESPONDWINDOWHANDLE, Application.MainForm.Handle); end; MI_RESPONDWINDOWHANDLE: // The running instance has returned its main window handle, // so we need to focus it and go away. begin SetForegroundWindow(HWND(lParam)); Application.Terminate; end; end; end // Otherwise, pass message on to old window proc else Result := CallWindowProc(WProc, Handle, Msg, wParam, lParam); end;procedure SubClassApplication; begin // We subclass Application window procedure so that // Application.OnMessage remains available for user. WProc := TFNWndProc(SetWindowLong(Application.Handle, GWL_WNDPROC, Longint(@NewWndProc))); // Set appropriate error flag if error condition occurred if WProc = nil then MIError := MIError or MI_ERROR_FAILSUBCLASS; end;procedure DoFirstInstance; // This is called only for the first instance of the application begin // Create the mutex with the (hopefully) unique string MutHandle := CreateMutex(nil, False, UniqueAppStr); if MutHandle = 0 then MIError := MIError or MI_ERROR_CREATINGMUTEX; end;procedure BroadcastFocusMessage; // This is called when there is already an instance running. var BSMRecipients: DWORD; begin // Prevent main form from flashing Application.ShowMainForm := False; // Post message to try to establish a dialogue with previous instance BSMRecipients := BSM_APPLICATIONS; BroadCastSystemMessage(BSF_IGNORECURRENTTASK or BSF_POSTMESSAGE, @BSMRecipients, MessageID, MI_QUERYWINDOWHANDLE, Application.Handle); end;procedure InitInstance; begin SubClassApplication; // hook application message loop MutHandle := OpenMutex(MUTEX_ALL_ACCESS, False, UniqueAppStr); if MutHandle = 0 then // Mutex object has not yet been created, meaning that no previous // instance has been created. DoFirstInstance else BroadcastFocusMessage; end;initialization MessageID := RegisterWindowMessage(UniqueAppStr); InitInstance; finalization // Restore old application window procedure if WProc <> Nil then SetWindowLong(Application.Handle, GWL_WNDPROC, LongInt(WProc)); if MutHandle <> 0 then CloseHandle(MutHandle); // Free mutex end.
Forms,
Controls,
......{$R *.RES}
var
HMuTex:HWnd;
Ret:Integer;begin //使程序只运行一次 Added by HGB
HMuTex:=CreateMuTex(nil,false,'Mutex_JSTRD_Application');
Ret:=GetLastError;
if Ret <> Error_Already_Exists then
begin
Application.Initialize;
Application.CreateForm(TForm1, Form1);
.....
Application.Run;
end
else
begin
ReleaseMuTex(HMuTex);
MessageBox(0,'程序已经启动!','提示信息',MB_ICONINFORMATION);
end; end.
var
aHandle: THandle;{$R *.res}begin
Application.Initialize;
aHandle := FindWindow(nil, '我的程序');
if aHandle <> 0 then
begin
if IsIconic(aHandle) then
SendMessage(aHandle, WM_SYSCOMMAND, SC_RESTORE, 0);
SetForeGroundWindow(aHandle);
Application.Terminate;
Exit;
end; Application.Title := '我的程序';
Application.CreateForm(TfrmSec, frmSec);
Application.Run;
end.
var
HWndCalculator : HWnd;
begin
HWndCalculator := FindWindow(nil, 'P_PublicHouse');
if HWndCalculator<>0 then
begin
application.message('此程序已经启动');
exit;
end;
end;
CreateMutex(nil,true,'我的程序');
if GetLastError = ERROR_ALREADY_EXISTS then
Application.Terminate;
将这段程序加在程序的FormCreate中就可以了!
if GetLastError = ERROR_ALREADY_EXISTS then
begin
MessageBox(0, PChar(SAlreadyRunning), SApplicationName, MB_ICONERROR);
Halt;
end;
MI_QUERYWINDOWHANDLE = 1;
MI_RESPONDWINDOWHANDLE = 2; MI_ERROR_NONE = 0;
MI_ERROR_FAILSUBCLASS = 1;
MI_ERROR_CREATINGMUTEX = 2;// Call this function to determine if error occurred in startup.
// Value will be one or more of the MI_ERROR_* error flags.
function GetMIError: Integer;implementationuses Forms, Windows, SysUtils;const
UniqueAppStr = 'ShuanYuan_SoftWare';var
MessageId: Integer;
WProc: TFNWndProc;
MutHandle: THandle;
MIError: Integer;function GetMIError: Integer;
begin
Result := MIError;
end;function NewWndProc(Handle: HWND; Msg: Integer; wParam, lParam: Longint):
Longint; stdcall;
begin
Result := 0;
// If this is the registered message...
if Msg = MessageID then
begin
case wParam of
MI_QUERYWINDOWHANDLE:
// A new instance is asking for main window handle in order
// to focus the main window, so normalize app and send back
// message with main window handle.
begin
if IsIconic(Application.Handle) then
begin
Application.MainForm.WindowState := wsNormal;
Application.Restore;
end;
PostMessage(HWND(lParam), MessageID, MI_RESPONDWINDOWHANDLE,
Application.MainForm.Handle);
end;
MI_RESPONDWINDOWHANDLE:
// The running instance has returned its main window handle,
// so we need to focus it and go away.
begin
SetForegroundWindow(HWND(lParam));
Application.Terminate;
end;
end;
end
// Otherwise, pass message on to old window proc
else
Result := CallWindowProc(WProc, Handle, Msg, wParam, lParam);
end;procedure SubClassApplication;
begin
// We subclass Application window procedure so that
// Application.OnMessage remains available for user.
WProc := TFNWndProc(SetWindowLong(Application.Handle, GWL_WNDPROC,
Longint(@NewWndProc)));
// Set appropriate error flag if error condition occurred
if WProc = nil then
MIError := MIError or MI_ERROR_FAILSUBCLASS;
end;procedure DoFirstInstance;
// This is called only for the first instance of the application
begin
// Create the mutex with the (hopefully) unique string
MutHandle := CreateMutex(nil, False, UniqueAppStr);
if MutHandle = 0 then
MIError := MIError or MI_ERROR_CREATINGMUTEX;
end;procedure BroadcastFocusMessage;
// This is called when there is already an instance running.
var
BSMRecipients: DWORD;
begin
// Prevent main form from flashing
Application.ShowMainForm := False;
// Post message to try to establish a dialogue with previous instance
BSMRecipients := BSM_APPLICATIONS;
BroadCastSystemMessage(BSF_IGNORECURRENTTASK or BSF_POSTMESSAGE,
@BSMRecipients, MessageID, MI_QUERYWINDOWHANDLE,
Application.Handle);
end;procedure InitInstance;
begin
SubClassApplication; // hook application message loop
MutHandle := OpenMutex(MUTEX_ALL_ACCESS, False, UniqueAppStr);
if MutHandle = 0 then
// Mutex object has not yet been created, meaning that no previous
// instance has been created.
DoFirstInstance
else
BroadcastFocusMessage;
end;initialization
MessageID := RegisterWindowMessage(UniqueAppStr);
InitInstance;
finalization
// Restore old application window procedure
if WProc <> Nil then
SetWindowLong(Application.Handle, GWL_WNDPROC, LongInt(WProc));
if MutHandle <> 0 then CloseHandle(MutHandle); // Free mutex
end.