How can I get other processes' information with Delphi? - delphi

Question

I want to make a Task Manager program that displays this information:
Image name
memory usage
PID
How can I do this?

Answer 1

You don't need the J(WS)CL therefore, there is a simple WinAPI call that does almost all you want, and this is CreateToolhelp32Snapshot. To get a snapshot of all running processes, you have to call it as follows:
var
snapshot: THandle;
begin
snapshot := CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);
Now you have a list of all running processes. You can navigate through this list with the Process32First and Process32Next functions, the list entries are PROCESSENTRY32-structures (which contain, amongst others, the process ID and image name).
uses
Windows, TLHelp32, SysUtils;
var
snapshot: THandle;
ProcEntry: TProcessEntry32;
s: String;
begin
snapshot := CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);
if (snapshot <> INVALID_HANDLE_VALUE) then begin
ProcEntry.dwSize := SizeOf(ProcessEntry32);
if (Process32First(snapshot, ProcEntry)) then begin
s := ProcEntry.szExeFile;
// s contains image name of the first process
while Process32Next(snapshot, ProcEntry) do begin
s := ProcEntry.szExeFile;
// s contains image name of the current process
end;
end;
end;
CloseHandle(snapshot);
However, memory consumption information doesn't seem to be included, but you can get this via another simple API call, GetProcessMemoryInfo
uses
psAPI;
var
pmc: TProcessMemoryCounters;
begin
pmc.cb := SizeOf(pmc) ;
if GetProcessMemoryInfo(processID, #pmc, SizeOf(pmc)) then
// Usage in Bytes: pmc.WorkingSetSize
else
// fail
You just have to call this function with the process IDs retrieved from the snapshot.

Answer 2

Use the PSAPI (Process Status API).
The open source JCL has a Delphi wrapper for the PSAPI.
There are some more good stackoverflow Delphi PSAPI questions you can check for answers.
--jeroen

Answer 3

you can use the WMI Win32_Process class to get all the running process info. addtionally you can check the Win32_PerfFormattedData_PerfProc_Process class to get the performance counters related to CPU and memory usage.
Check this sample
program WMIProcessInfo;
{$APPTYPE CONSOLE}
uses
SysUtils
,ActiveX
,ComObj
,Variants;
procedure GetWin32_Process;
var
objWMIService : OLEVariant;
colItems : OLEVariant;
colItem : OLEVariant;
oEnum : IEnumvariant;
iValue : LongWord;
User : OLEVariant;
Domain : OLEVariant;
function GetWMIObject(const objectName: String): IDispatch;
var
chEaten: Integer;
BindCtx: IBindCtx;
Moniker: IMoniker;
begin
OleCheck(CreateBindCtx(0, bindCtx));
OleCheck(MkParseDisplayName(BindCtx, StringToOleStr(objectName), chEaten, Moniker));
OleCheck(Moniker.BindToObject(BindCtx, nil, IDispatch, Result));
end;
begin
objWMIService := GetWMIObject('winmgmts:\\localhost\root\cimv2');
colItems := objWMIService.ExecQuery('SELECT * FROM Win32_Process','WQL',0);
oEnum := IUnknown(colItems._NewEnum) as IEnumVariant;
WriteLn(Format('%-20s %6s %10s %10s %10s',['Caption','PID','User','Domain','Working Set ( Kb Memory)']));
while oEnum.Next(1, colItem, iValue) = 0 do
begin
colItem.GetOwner(User,Domain);
if colItem.GetOwner( User, Domain ) =0 then //get the user and domain
WriteLn(Format('%-20s %6s %10s %10s %10s',[colItem.Caption,colItem.ProcessId,User,Domain,colItem.WorkingSetSize / 1024]))
else
WriteLn(Format('%-20s %6s %10s %10s %10s',[colItem.Caption,colItem.ProcessId,'','',colItem.WorkingSetSize / 1024]));
end;
end;
begin
try
CoInitialize(nil);
try
GetWin32_Process;
Readln;
finally
CoUninitialize;
end;
except
on E:Exception do
Begin
Writeln(E.Classname, ': ', E.Message);
Readln;
End;
end;
end.

Answer 4

In Jwscl there is a class that can do this for you (JwsclTerminalServer):
var
ATerminalServer: TJwTerminalServer;
i: Integer;
begin
// Create Terminal Server instance and allocate memory for it
ATerminalServer := TjwTerminalServer.Create;
// Set servername (only in case of remote server)
ATerminalServer.Server := 'TS001';
// Remember that EnumerateProcesses will automatically connect to the
// Terminal Server for you. The connect function raises an Exception
// if the connection attempt was unsuccessfull, so better use try..except
try
if ATerminalServer.EnumerateProcesses then
begin
// Now loop through the list
for i := 0 to ATerminalServer.Processes.Count - 1 do
begin
Memo1.Lines.Add(ATerminalServer.Processes[i].ProcessName);
end;
end;
except
on E: EJwsclWinCallFailedException do
begin
// Handle Exception here
end;
end;
// Free Memory
ATerminalServer.Free;
end;
Although the unit is aimed at Terminal Server this part works both with and without and as a bonus you can use it on remote systems as well.
For each process detailed information is returned, check the docs for details.
For memory usage you can use the ProcessMemUsage and ProcessVirtualSize properties, for the Pid there is the ProcessId property

Answer 5

ProcessInfo provides basic information about running processes in Windows. It is open-source, and contains a demo of a task manager.