Best Way to Release Excel Interop com Object

Question

Experts, Please let me know the best way I can do this...

I am working on a VB.Net application that uses the Microsoft.Office.Interop.Excel Object Library to create

Answer 1

I share VB.net code:

Imports System.Runtime.InteropServices
Namespace Jobs

Public Class Job
    Implements IDisposable

    ', 
    CallingConvention:=CallingConvention.Cdecl)>
    Shared Function CreateJobObject(a As IntPtr, lpName As String) As IntPtr
    End Function

    
    Public Shared Function SetInformationJobObject(hJob As IntPtr, infoType As 
    JobObjectInfoType, lpJobObjectInfo As IntPtr, cbJobObjectInfoLength As UInteger) As Boolean
    End Function

    
    Public Shared Function CloseHandle(Token As IntPtr) As Boolean
    End Function

    
    Public Shared Function AssignProcessToJobObject(job As IntPtr, process As IntPtr) as Boolean
    End Function

    Private m_handle As IntPtr
    Private m_disposed As Boolean = False

    Public Sub New()

        m_handle = CreateJobObject(IntPtr.Zero, Nothing)

        Dim info As JOBOBJECT_BASIC_LIMIT_INFORMATION = New JOBOBJECT_BASIC_LIMIT_INFORMATION()
        info.LimitFlags = &H2000

        Dim extendedInfo = New JOBOBJECT_EXTENDED_LIMIT_INFORMATION()
        extendedInfo.BasicLimitInformation = info

        Dim length As Integer = Marshal.SizeOf(GetType(JOBOBJECT_EXTENDED_LIMIT_INFORMATION))
        Dim extendedInfoPtr As IntPtr = Marshal.AllocHGlobal(length)
        Marshal.StructureToPtr(extendedInfo, extendedInfoPtr, False)

        If (Not SetInformationJobObject(m_handle, JobObjectInfoType.ExtendedLimitInformation, extendedInfoPtr, length)) Then
            Throw New Exception(String.Format("Unable to set information.  Error: {0}", Marshal.GetLastWin32Error()))
        End If
    End Sub

#Region "IDisposableMembers"

    Public Sub Dispose() Implements IDisposable.Dispose
        Dispose(True)
        GC.SuppressFinalize(Me)
    End Sub

#End Region
    Private Sub Dispose(disposing As Boolean)
        If m_disposed Then
            Return
        End If
        If disposing Then
        End If
        Close()
        m_disposed = True
    End Sub

    Public Sub Close()
        CloseHandle(m_handle)
        m_handle = IntPtr.Zero
    End Sub

    Public Function AddProcess(handle As IntPtr) As Boolean
        Return AssignProcessToJobObject(m_handle, handle)
    End Function

End Class

Public Enum JobObjectInfoType
    AssociateCompletionPortInformation = 7
    BasicLimitInformation = 2
    BasicUIRestrictions = 4
    EndOfJobTimeInformation = 6
    ExtendedLimitInformation = 9
    SecurityLimitInformation = 5
    GroupInformation = 11
End Enum


Public Structure SECURITY_ATTRIBUTES
    Public nLength As Integer
    Public lpSecurityDescriptor As IntPtr
    Public bInheritHandle As Integer
End Structure


Structure JOBOBJECT_BASIC_LIMIT_INFORMATION
    Public PerProcessUserTimeLimit As Int64
    Public PerJobUserTimeLimit As Int64
    Public LimitFlags As Int16
    Public MinimumWorkingSetSize As UInt32
    Public MaximumWorkingSetSize As UInt32
    Public ActiveProcessLimit As Int16
    Public Affinity As Int64
    Public PriorityClass As Int16
    Public SchedulingClass As Int16
End Structure


Structure IO_COUNTERS
    Public ReadOperationCount As UInt64
    Public WriteOperationCount As UInt64
    Public OtherOperationCount As UInt64
    Public ReadTransferCount As UInt64
    Public WriteTransferCount As UInt64
    Public OtherTransferCount As UInt64
End Structure


Structure JOBOBJECT_EXTENDED_LIMIT_INFORMATION
    Public BasicLimitInformation As JOBOBJECT_BASIC_LIMIT_INFORMATION
    Public IoInfo As IO_COUNTERS
    Public ProcessMemoryLimit As UInt32
    Public JobMemoryLimit As UInt32
    Public PeakProcessMemoryUsed As UInt32
    Public PeakJobMemoryUsed As UInt32
End Structure

End Namespace

And, in the class where you plan to implement:

Public Shared Function GetWindowThreadProcessId(hWnd As IntPtr, ByRef lpdwProcessId As UInteger) As UInteger
End Function


'Implements
Dim oExcelApp = New Microsoft.Office.Interop.Excel.Application
Dim job As Jobs.Job = New Jobs.Job()
Dim pid As UInteger = 0
GetWindowThreadProcessId(New IntPtr(oExcelApp.Hwnd), pid)
job.AddProcess(Process.GetProcessById(pid).Handle)

oExcelApp.Workbooks.Open(RutaArchivoExcel)

'Code work code here

oExcelApp.Workbooks(1).Close()
oExcelApp.Quit()

'Then Dispose correctly the excel app and windows distroy appropiately the process
job.Dispose()

i test this with Microsoft Excel 2016.