[C]ProcessID, Process Handle, Window Handle 之间的互相转换

// Get ProcessID By ProgramName (Include Path or Not Include)   
function GetPIDByProgramName(const APName: string): THandle;   
// Get Window Handle By ProgramName (Include Path or Not Include)   
function GetHWndByProgramName(const APName: string): THandle;   
// Get Window Handle By ProcessID   
function GetHWndByPID(const hPID: THandle): THandle;   
// Get ProcessID By Window Handle   
function GetPIDByHWnd(const hWnd: THandle): THandle;   
// Get Process Handle By Window Handle   
function GetProcessHndByHWnd(const hWnd: THandle): THandle;   
// Get Process Handle By Process ID   
function GetProcessHndByPID(const hAPID: THandle): THandle;   

// Get Window Handle By ProgramName (Include Path or Not Include)   
function GetHWndByProgramName(const APName: string): THandle;   
begin   
     Result:=GetHWndByPID(GetPIDByProgramName(APName));   
end;   

// Get Process Handle By Window Handle   
function GetProcessHndByHWnd(const hWnd: THandle): THandle;   
var   
     PID: DWORD;   
     AhProcess: THandle;   
begin   
     if hWnd<>0 then   
     begin   
     GetWindowThreadProcessID(hWnd, @PID);   
     AhProcess := OpenProcess(PROCESS_ALL_ACCESS, false, PID);   
     Result:=AhProcess;   
     CloseHandle(AhProcess);   
     end   
     else  
     Result:=0;   
end;   

// Get Process Handle By Process ID   
function GetProcessHndByPID(const hAPID: THandle): THandle;   
var   
     AhProcess: THandle;   
begin   
     if hAPID<>0 then   
     begin   
     AhProcess := OpenProcess(PROCESS_ALL_ACCESS, false, hAPID);   
     Result:=AhProcess;   
     CloseHandle(AhProcess);   
     end   
     else  
     Result:=0;   
end;   

// Get Window Handle By ProcessID   
function GetPIDByHWnd(const hWnd: THandle): THandle;   
var   
     PID: DWORD;   
begin   
     if hWnd<>0 then   
     begin   
     GetWindowThreadProcessID(hWnd, @PID);   
     Result:=PID;   
     end   
     else  
     Result:=0;   
end;   

// Get Window Handle By ProcessID   
function GetHWndByPID(const hPID: THandle): THandle;   
type   
     PEnumInfo = ^TEnumInfo;   
     TEnumInfo = record   
     ProcessID: DWORD;   
     HWND: THandle;   
     end;   

     function EnumWindowsProc(Wnd: DWORD; var EI: TEnumInfo): Bool; stdcall;   
     var   
     PID: DWORD;   
     begin   
     GetWindowThreadProcessID(Wnd, @PID);   
     Result := (PID <> EI.ProcessID) or   
         (not IsWindowVisible(WND)) or   
         (not IsWindowEnabled(WND));   

     if not Result then EI.HWND := WND; //break on return FALSE 所以要反向檢查   
     end;   

     function FindMainWindow(PID: DWORD): DWORD;   
     var   
     EI: TEnumInfo;   
     begin   
     EI.ProcessID := PID;   
     EI.HWND := 0;   
     EnumWindows(@EnumWindowsProc, Integer(@EI));   
     Result := EI.HWND;   
     end;   
begin   
     if hPID<>0 then   
     Result:=FindMainWindow(hPID)   
     else  
     Result:=0;   
end;   

// Get ProcessID By ProgramName (Include Path or Not Include)   
function GetPIDByProgramName(const APName: string): THandle;   
var   
     isFound: boolean;   
     AHandle, AhProcess: THandle;   
     ProcessEntry32: TProcessEntry32;   
     APath: array[0..MAX_PATH] of char;   
begin   
     try  
     Result := 0;   
     AHandle := CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);   
     ProcessEntry32.dwSize := Sizeof(ProcessEntry32);   
     isFound := Process32First(AHandle, ProcessEntry32);   

     while isFound do  
     begin   
         AhProcess := OpenProcess(PROCESS_QUERY_INFORMATION or PROCESS_VM_READ,   
         false, ProcessEntry32.th32ProcessID);   
         GetModuleFileNameEx(AhProcess, 0, @APath[0], sizeof(APath));   

         if (UpperCase(StrPas(APath)) = UpperCase(APName)) or   
         (UpperCase(StrPas(ProcessEntry32.szExeFile)) = UpperCase(APName)) then   
         begin   
         Result := ProcessEntry32.th32ProcessID;   
         break;   
         end;   
         isFound := Process32Next(AHandle, ProcessEntry32);   
         CloseHandle(AhProcess);   
     end;   
     finally   
     CloseHandle(AHandle);   
     end;   
end;