Start, Stop and Pause NT Services

Option Explicit

Public Enum eServiceState
essStopService
essStartService
essPauseService
End Enum

Private Declare Function CloseServiceHandle Lib "advapi32.dll" (ByVal hSCObject As Long) As Long
Private Declare Function ControlService Lib "advapi32.dll" (ByVal lHwndService As Long, ByVal dwControl As Long, lpServiceStatus As SERVICE_STATUS) As Long
Private Declare Function OpenSCManager Lib "advapi32.dll" Alias "OpenSCManagerA" (ByVal lpMachineName As String, ByVal lpDatabaseName As String, ByVal dwDesiredAccess As Long) As Long
Private Declare Function OpenService Lib "advapi32.dll" Alias "OpenServiceA" (ByVal hSCManager As Long, ByVal lpServiceName As String, ByVal dwDesiredAccess As Long) As Long
Private Declare Function QueryServiceStatus Lib "advapi32.dll" (ByVal lHwndService As Long, lpServiceStatus As SERVICE_STATUS) As Long
Private Declare Function StartService Lib "advapi32.dll" Alias "StartServiceA" (ByVal lHwndService As Long, ByVal dwNumServiceArgs As Long, ByVal lpServiceArgVectors As Long) As Long

Private Const SERVICES_ACTIVE_DATABASE = "ServicesActive"
Private Const SERVICE_CONTROL_STOP = &H1
Private Const SERVICE_CONTROL_PAUSE = &H2
Private Const SERVICE_STOPPED = &H1
Private Const SERVICE_START_PENDING = &H2
Private Const SERVICE_STOP_PENDING = &H3
Private Const SERVICE_RUNNING = &H4
Private Const SERVICE_CONTINUE_PENDING = &H5
Private Const SERVICE_PAUSE_PENDING = &H6
Private Const SERVICE_PAUSED = &H7
Private Const STANDARD_RIGHTS_REQUIRED = &HF0000
Private Const SC_MANAGER_CONNECT = &H1
Private Const SC_MANAGER_CREATE_SERVICE = &H2
Private Const SC_MANAGER_ENUMERATE_SERVICE = &H4
Private Const SC_MANAGER_LOCK = &H8
Private Const SC_MANAGER_QUERY_LOCK_STATUS = &H10
Private Const SC_MANAGER_MODIFY_BOOT_CONFIG = &H20
Private Const SC_MANAGER_ALL_ACCESS = (STANDARD_RIGHTS_REQUIRED Or SC_MANAGER_CONNECT Or SC_MANAGER_CREATE_SERVICE Or SC_MANAGER_ENUMERATE_SERVICE Or SC_MANAGER_LOCK Or SC_MANAGER_QUERY_LOCK_STATUS Or SC_MANAGER_MODIFY_BOOT_CONFIG)
Private Const SERVICE_QUERY_CONFIG = &H1
Private Const SERVICE_CHANGE_CONFIG = &H2
Private Const SERVICE_QUERY_STATUS = &H4
Private Const SERVICE_ENUMERATE_DEPENDENTS = &H8
Private Const SERVICE_START = &H10
Private Const SERVICE_STOP = &H20
Private Const SERVICE_PAUSE_CONTINUE = &H40
Private Const SERVICE_INTERROGATE = &H80
Private Const SERVICE_USER_DEFINED_CONTROL = &H100
Private Const SERVICE_ALL_ACCESS = (STANDARD_RIGHTS_REQUIRED Or SERVICE_QUERY_CONFIG Or SERVICE_CHANGE_CONFIG Or SERVICE_QUERY_STATUS Or SERVICE_ENUMERATE_DEPENDENTS Or SERVICE_START Or SERVICE_STOP Or SERVICE_PAUSE_CONTINUE Or SERVICE_INTERROGATE Or SERVICE_USER_DEFINED_CONTROL)

Private Type SERVICE_STATUS
dwServiceType As Long
dwCurrentState As Long
dwControlsAccepted As Long
dwWin32ExitCode As Long
dwServiceSpecificExitCode As Long
dwCheckPoint As Long
dwWaitHint As Long
End Type


'Purpose : Returns the status of a NT Service
'Inputs : sServiceName The name of the service to test
' [sComputerName] The name of the machine to test the service status on.
' If unspecified uses the local machine
'Outputs : Returns a English description of the service status


Public Function ServiceStatus(sServiceName As String, Optional sComputerName As String) As String
Dim tServiceStat As SERVICE_STATUS
Dim lHwndSManager As Long
Dim lHwndService As Long
Dim hServiceStatus As Long

'Check the input data
If InStr(1, sServiceName, " ") Then
Debug.Print "Service names cannot contain spaces. Use the 'Service Name' of the service, not the 'Display Name'"
Exit Function
End If

ServiceStatus = ""
'Open the service manager
lHwndSManager = OpenSCManager(sComputerName, SERVICES_ACTIVE_DATABASE, SC_MANAGER_ALL_ACCESS)
If lHwndSManager <> 0 Then
'Open the service
lHwndService = OpenService(lHwndSManager, sServiceName, SERVICE_ALL_ACCESS)
If lHwndService <> 0 Then
'Query the service
hServiceStatus = QueryServiceStatus(lHwndService, tServiceStat)
If hServiceStatus <> 0 Then
Select Case tServiceStat.dwCurrentState
Case SERVICE_STOPPED
ServiceStatus = "Stopped"
Case SERVICE_START_PENDING
ServiceStatus = "Start Pending"
Case SERVICE_STOP_PENDING
ServiceStatus = "Stop Pending"
Case SERVICE_RUNNING
ServiceStatus = "Running"
Case SERVICE_CONTINUE_PENDING
ServiceStatus = "Coninue Pending"
Case SERVICE_PAUSE_PENDING
ServiceStatus = "Pause Pending"
Case SERVICE_PAUSED
ServiceStatus = "Paused"
End Select
End If
'Close the service
CloseServiceHandle lHwndService
End If
'Close the service mananger
CloseServiceHandle lHwndSManager
End If
End Function

'Purpose : Changes the state of an NT Service
'Inputs : sServiceName The name of the service to test
' [sComputerName] The name of the machine to test the service status on.
' If unspecified uses the local machine
'Outputs : N/A


Public Function ServiceStateChange(sServiceName As String, eState As eServiceState, Optional sComputerName As String) As Boolean
Dim tServiceStatus As SERVICE_STATUS
Dim lHwndSManager As Long
Dim lHwndService As Long
Dim lRes As Long

'Check the input data
If InStr(1, sServiceName, " ") Then
Debug.Print "Service names cannot contain spaces. Use the 'Service Name' of the service, not the 'Display Name'"
ServiceStateChange = False
Exit Function
End If

'Open the service manager
lHwndSManager = OpenSCManager(sComputerName, SERVICES_ACTIVE_DATABASE, SC_MANAGER_ALL_ACCESS)
If lHwndSManager <> 0 Then
'Open the service
lHwndService = OpenService(lHwndSManager, sServiceName, SERVICE_ALL_ACCESS)
If lHwndService <> 0 Then
Select Case eState
Case essPauseService
'Pause the service
lRes = ControlService(lHwndService, SERVICE_CONTROL_PAUSE, tServiceStatus)
Case essStartService
'Start the service
lRes = StartService(lHwndService, 0, 0)
Case essStopService
lRes = ControlService(lHwndService, SERVICE_CONTROL_STOP, tServiceStatus)
Case Else
Debug.Print "Invalid Service State"
Debug.Assert False
End Select

If lRes Then
'Success
ServiceStateChange = True
Else
'Failed
ServiceStateChange = False
Debug.Print "Error in ServiceStateChange: " & Err.LastDllError
Debug.Assert False
End If
CloseServiceHandle lHwndService
End If
CloseServiceHandle lHwndSManager
Else
Debug.Print "Failed to open service mananger!"
Debug.Assert False
ServiceStateChange = False
End If
End Function

'Demonstration routine using the "Windows Time" service
Sub Test()
Dim sStatus As String

sStatus = ServiceStatus("W32Time")
Debug.Print "Event Log is now " & sStatus

Call ServiceStateChange("W32Time", essStopService)
sStatus = ServiceStatus("W32Time")
Debug.Print "Event Log is now " & sStatus

Call ServiceStateChange("W32Time", essStartService)
sStatus = ServiceStatus("Eventlog")
Debug.Print "Event Log is now " & sStatus
End Sub

No comments:

Post a Comment

Subscribe to: Post Comments (Atom)

Visual Basic-6 has emerged as one of the standard Windows Programming Language and it has become a must for all Software people for developing Applications in Visual Environment. So it is, one must learn Visual Basic-6.

What is our Objective in this Courseware?

The Overall Objective in this Courseware is to give a Hands-on Approach to develop different projects in Visual Basic-6.0 using intrinsic, professional and user–created ActiveX controls and also develop projects using databases, DAO’s, ADO’s, DLL’s, Documents, Crystal Reports etc. covering almost all the essential features of VB-6 Professional Edition. After reading one lesson any interested reader will be able to get complete hands-on experience with the VB project and get a sense of fulfilment and achievement. Learning by doing is the motto with which this courseware is written. After giving a short introduction about VB-6 we will explain how to create and execute a project in VB using some intrinsic ActiveX controls. Creating and executing projects will be the central theme of all the lessons which we will be giving in this courseware.

What is Visual Basic-6?

Visual Basic-6 has its origin in Basic which was developed round about the year 1960, when high level languages were just being introduced to the computer community. Microsoft has made it extremely powerful by gearing all its good features to the Windows environment. Starting with the version 3 and then with 4, and then with 6, Visual Basic is now at version 6. Basic is a Procedure Oriented Language intended to implement single tasks in text based environment whereas Visual Basic is an Event Driven Language intended to implement Projects or Applications containing multiple tasks in Windows Environment.

What can Visual Basic do for you?

Visual Basic can serve as an ideal front end tool for the clients to interact. It has got connectivity mechanisms for all types of databases situated far and wide in a network and so it can cater to the needs of a large body of clients. Using the latest ActiveX technologies, it can integrate the functionalities provided by other applications like Word Excel and other Windows. Its internet capabilities provide easy access to documents and applications across the internet. Above all it embodies the Object Oriented Technology, which is the cutting edge technology for all the present day developments in the Software World. The final application is a true EXE file and so can be freely distributed.


Structure of VB-6 Projects:

We said earlier that VB-6 implements projects or applications. A project is developed using one or more Forms. A Form is simply a window containing one or more Controls. Controls in VB consist of labels, text boxes, list boxes, combo boxes, scroll bars etc. which are the constituents of windows environment. It is only the controls that give VB, its immense power and so there is a lot of interest in creating more and more powerful controls. ActiveX controls mark a significant development in controls technology. In fact all controls in VB-6 are ActiveX controls, which have the extension .ocx. These controls have properties whose values can be initialized at design time and also varied during run time. The properties are something like variables. The controls are activated by codes written in a high level language. By associating our problem variables with the properties of the controls, our problem variables can be manipulated to give the problem solution. In summary we can say that a VB project is made of forms, controls and their properties and codes.

Integrated Development Environment:

The working environment in VB is often referred to as the Integrated Development Environment or IDE, because it integrates many different functions such as design, editing, compiling and debugging within a common environment. Since all our projects are developed only in the IDE, let us now have a brief look at its features. You will be able to understand their uses at the time of building projects. The VB IDE looks as shown in the figure.