Does FreePascal have a WMI Query library?

[jma_sp]

Thanks,

It´s very useful because WMI let´s obtain a lot of information. By example it can return the total amount of physical memory: . This one is a very frequent question in Internet

GetWMIInfo('Win32_COMPUTERSYSTEM', ['TotalPhysicalMemory']);

Saludos.

[ASerge]

Can you notice the difference ?

Of course. Try must be used AFTER the resource allocation. But to write code with errors based on incorrect application is also wrong.

[molly]

@ASerge:
You are correct in that code can become a bit awkward when attempting to handle such exception correctly.

But what would you propose then ?

I'm uncomfortable with the solution as shown by you earlier, because it is usually end-user responsibility to act on exceptions.

In addition to that. It might be that only one 'entry' went wrong while all other entries are (still) valid. It would be unwise to clear the whole objectlist for that ?

There probably is/was a good reason that Jurassic Pork left things open as it currently is.

Note that J.P. 's unit is only a small helper routine that offer you quick WMI access. A better choice would probably be to use an implementation based on something like a dataset.

I'm all for improving things, that is why i contributed. In case you have something to offer/contribute then please feel free to contact J.P. and make an offer. He's a very reasonable person (and after all, it is his idea/project. e.g. my vote doesn't really count).

[ASerge]

@ASerge:
I'm uncomfortable with the solution as shown by you earlier, because it is usually end-user responsibility to act on exceptions.
In addition to that. It might be that only one 'entry' went wrong while all other entries are (still) valid. It would be unwise to clear the whole objectlist for that ?

Why not? Once the memory is allocated inside the function, when internal errors - it is must to clean.
In my opinion it is more convenient when cleaning the one, who allocate. But if we delegate to function allocate only, I prefer this approach:

Code: Pascal  [Select][+][-]

1. function ProducedSomeData(const ByParams: TInputParamsClass;
2.   out DataHolder: TDataHolderClass): Boolean;
3. //...
4. begin
5.   try
6.     DataHolder := TDataHolderClass.Create({...});
7.     //...
8.     Result := True;
9.   except
10.     DataHolder.Free; // Escape memory leak
11.     raise; // End-user responsibility to act on exceptions
12.     // { Or handle this on their own} DataHolder := nil; Result := False;
13.   end;
14. end;
15.  
16. procedure UseSomeData;
17. //...
18. begin
19.   if ProducedSomeData(InputParams, DataHolder) then
20.   try
21.     //...
22.   finally
23.     DataHolder.Free;
24.   end;
25. end;                    

[vonskie]

I have this code in vbscript

Sub networkcard
   
   Set colItems = objWMIService.ExecQuery _
   ("Select * From Win32_NetworkAdapterConfiguration Where IPEnabled = True")
   
   For Each objItem In colItems
      
      If InStr(objItem.Description,"WAN")=0 Then
         
         
         report=report  & "Description: " & objItem.Description &vbCrLf
         report=report  & "IP Address: " &vbCrLf
         
         
         For Each strAddress In objItem.IPAddress
            report=report  & strAddress & vbCrLf
         Next
         
      End If
      
   Next
   
End Sub

I have gotten this far but I do not know how to do the "strAddress In objItem.IPAddress" using the wmi call please help!

PropNamesNetworkAdapterConfiguration: array[0..0] of string = ('Description');

WMIResult := GetWMIInfo('Win32_NetworkAdapterConfiguration',
        PropNamesNetworkAdapterConfiguration, 'Where IPEnabled = True');
      for i := 0 to Pred(WMIResult.Count) do
      begin
        REPORT := report + '================================================' + #13#10;
        for PropNamesIndex := Low(PropNamesNetworkAdapterConfiguration) to High(PropNamesNetworkAdapterConfiguration) do
        begin
          REPORT := report + TStringList(WMIResult).Names[PropNamesIndex] +
            ' : ' + TStringList(WMIResult).ValueFromIndex[PropNamesIndex] + #13#10;
        end;
      end;

      // Clean up
      WMIResult.Free;     

Please help!

[molly]

Please don't ignore the warnings that the compiler throws at you as they give you a clue.

Not sure if this is what you meant to do:

Code: Pascal  [Select][+][-]

1. program example_nwadaptercfg;
2.  
3. {$MODE OBJFPC}{$H+}
4.  
5. uses
6.   classes, contnrs, utilwmi;
7.  
8. procedure DoIt;
9. var
10.   WMIResult         : TFPObjectList;
11.   i                 : Integer;
12.   PropNamesIndex    : Integer;
13.   PropNames         : Array[0..1] of String = ( 'Description', 'IPAddress' );
14. begin
15.   WMIResult := GetWMIInfo('Win32_NetworkAdapterConfiguration', PropNames, 'Where IPEnabled = True');
16.  
17.   for i := 0 to Pred(WMIResult.Count) do
18.   begin
19.     WriteLn('================================================');
20.  
21.     for PropNamesIndex := Low(PropNames) to High(PropNames) do
22.     begin
23.       WriteLn(TStringList(WMIResult[i]).Names[PropNamesIndex] + ' : ' +
24.               TStringList(WMIResult[i]).ValueFromIndex[PropNamesIndex]);
25.     end;
26.   end;
27.   // Clean up
28.   WMIResult.Free;
29. end;
30.  
31. begin
32.   DoIt;
33. end.
34.  

[Thaddy]

Since when can you hardcast to a TStringlist? If that works it is by accident.... Tstringlist is not an array..... it is a class.

[rvk]

Since when can you hardcast to a TStringlist? If that works it is by accident.... Tstringlist is not an array..... it is a class.

Have you checked out what WMIResult := GetWMIInfo() really does before posting that comment ??

It creates a TFPObjectList of multiple TStringLists so the hardcast is perfectly legit.
(i.e. WMIResult[i] is a TStringList of itself)

[molly]

Indeed as rvk wrote, the objectlist contains stringlists.

There is much room for further improvements...

[molly]

Sorry ASerge, i seem to have missed your latest response 

Why not? Once the memory is allocated inside the function, when internal errors - it is must to clean.
In my opinion it is more convenient when cleaning the one, who allocate. But if we delegate to function allocate only, I prefer this approach:

Sure, but even better would be to have a separate wmi class that does everything internally (an act correctly when something goes wrong, e.g. not bother the user with it).

As said, there is much room for improvements. If you have something to offer then offer it to J.P. Because of the backwards compatibility with fpc 2.6.4 i have not given it very much additional thoughts (generics, operator overloading etc.).

There is a wmi dataset class floating around for Delphi. That could perhaps work as a good alternative for my clumsy coding ?

[9ep2rz]

Hi Jurassic Port,

Using utilwmi unit I can get serial number of hard drives but I want to get from a specific drive, because I have 2 hard drive in my computer.

Here is the code but I need to pass drive letter (D, F, H) and want to get physical serial number:

Code: Pascal  [Select][+][-]

1. procedure TForm1.Button1Click(Sender: TObject);
2.   var
3.     WMIResult         : TFPObjectList;
4.     WMIResult2         : TFPObjectList;
5.     f              : integer;
6.     retVal            : String;
7. begin
8.  WMIResult := GetWMIInfo('Win32_DiskDrive', ['DeviceID', 'SerialNumber']);
9.   for f := 0 to Pred(WMIResult.Count) do
10.   begin
11.     retVal := TStringList(WMIResult[f]).ValueFromIndex[0] + ' : ' + TStringList(WMIResult[f]).ValueFromIndex[1];
12.     Memo1.Lines.add(Retval);
13.   end;
14.  
15.   WMIResult.Free;
16. end;
17.  

Thanks,

[molly]

Here is the code but I need to pass drive letter (D, F, H) and want to get physical serial number:

Not possible to accomplish with using utilWMI.

Use your own instance of wmi and associate the proper objects to each other.  Hint: you need to parse things the other way around and in the end match your drive-letter. (DiskDrive -> Partition -> LogicalDisk -> DriveLetter -> DiskDrive.SerialNumber)

[Jurassic Pork]

hello,
utilwmi can only do Select WQL  Request.

Not possible to accomplish with using utilWMI.
Use your own instance of wmi and associate the proper objects to each other.  Hint: you need to parse things the other way around and in the end match your drive-letter. (DiskDrive -> Partition -> LogicalDisk -> DriveLetter -> DiskDrive.SerialNumber)

To do this , you must use Associators of WQL Request.
here is an example  :

Code: Pascal  [Select][+][-]

1. // uses  Variants,ActiveX, ComObj        ;
2. procedure TForm1.Button1Click(Sender: TObject);
3. const
4.   wbemFlagForwardOnly = $00000020;
5. var
6.   FSWbemLocator     : OLEVariant;
7.   FWMIService       : OLEVariant;
8.   wmiDiskDrives     : OLEVariant;
9.   wmiDiskPartitions : OLEVariant;
10.   wmiLogicalDisks   : OLEVariant;
11.   wmiDiskDrive      : OLEVariant;
12.   wmiDiskPartition  : OLEVariant;
13.   wmiLogicalDisk    : OLEVariant;
14.   oEnum             : IEnumvariant;
15.   oEnum2            : IEnumvariant;
16.   oEnum3            : IEnumvariant;
17.   iValue            : LongWord;
18.   DeviceID          : string;
19.   Partitions        : string;
20.   SerNum,SerNumByDriveLetter  : string;
21. begin;
22.   FSWbemLocator   := CreateOleObject('WbemScripting.SWbemLocator');
23.   FSWbemLocator.Security_.privileges.addasstring('sedebugprivilege', true);
24.   FWMIService   := FSWbemLocator.ConnectServer('localhost', 'root\CIMV2', '', '');
25.   FWMIService.Security_.ImpersonationLevel := 3;
26.   //Get the physical disk drive
27.   wmiDiskDrives := FWMIService.ExecQuery('SELECT Caption, DeviceID,SerialNumber FROM Win32_DiskDrive','WQL',wbemFlagForwardOnly);
28.   oEnum         := IUnknown(wmiDiskDrives._NewEnum) as IEnumVariant;
29.   while oEnum.Next(1, wmiDiskDrive, iValue) = 0 do
30.   begin
31.      SerNum := '';
32.      Memo1.Lines.add(wmiDiskDrive.Caption);
33.      if wmiDiskDrive.SerialNumber <> Null then
34.      SerNum := UpperCase(String( wmiDiskDrive.SerialNumber));
35.      Memo1.Lines.add('Serial Number : ' + SerNum  +
36.                      '  =  ' + HexStrToStr(SerNum));
37.  
38.      Partitions := '';
39.      //Use the disk drive device id to find associated partition
40.      DeviceID:=StringReplace(String(wmiDiskDrive.DeviceID),'\','\\',[rfReplaceAll]);
41.      wmiDiskPartitions := FWMIService.ExecQuery(
42.      WideString('ASSOCIATORS OF {Win32_DiskDrive.DeviceID="'+
43.      DeviceID+'"} WHERE AssocClass = Win32_DiskDriveToDiskPartition'),
44.      'WQL',wbemFlagForwardOnly);
45.      oEnum2          := IUnknown(wmiDiskPartitions._NewEnum) as IEnumVariant;
46.      while oEnum2.Next(1, wmiDiskPartition, iValue) = 0 do
47.      begin
48.         wmiLogicalDisks := FWMIService.ExecQuery(
49.         WideString('ASSOCIATORS OF {Win32_DiskPartition.DeviceID="'+
50.         String(wmiDiskPartition.DeviceID)+
51.         '"} WHERE AssocClass = Win32_LogicalDiskToPartition'),
52.         'WQL',wbemFlagForwardOnly);
53.         oEnum3          := IUnknown(wmiLogicalDisks._NewEnum) as IEnumVariant;
54.         while oEnum3.Next(1, wmiLogicalDisk, iValue) = 0 do
55.         begin
56.           if  (wmiLogicalDisk.DeviceID = 'C:') AND
57.           (wmiDiskDrive.SerialNumber <> Null)  then
58.           SerNumByDriveLetter :=   HexStrToStr(SerNum);
59.  
60.           Partitions := Partitions + String(wmiLogicalDisk.DeviceID)+ ' ,';
61.           wmiLogicalDisk:=Unassigned;
62.         end;
63.        wmiDiskPartition:=Unassigned;
64.      end;
65.     wmiDiskDrive:=Unassigned;
66.     Memo1.Lines.Append('Partitions : ' + Partitions);
67.     Memo1.Lines.add('=======================================');
68.   end;
69.     Memo1.Append('Disk Serial Number for C: is ' + SerNumByDriveLetter );
70. end;  

The function HexStrToStr is a code of ASerge :

Code: Pascal  [Select][+][-]

1. uses Classes;
2.  
3. function HexStrToStr(const HexStr: string): string;
4. var
5.   ResultLen: Integer;
6. begin
7.   ResultLen := Length(HexStr) div 2;
8.   SetLength(Result, ResultLen);
9.   if ResultLen > 0 then
10.     SetLength(Result, HexToBin(Pointer(HexStr), Pointer(Result), ResultLen));
11. end;

Friendly J.P

[9ep2rz]

Thanks Jurassi Pork,

It really helped me.