Office Add In Memory Limit - vb.net

Question

I am developing a set of Office add ins that reads and writes templates and other files from a locally stored serialized object. Until now it has been going well, however, since I have been stress testing it by writing big amounts of data to this local object, and loading it into memory when reading from it, I have been getting SystemOutOfMemory exceptions. I do clean memory out each time I am done with this object, but simply loading it into memory can cause the exception be thrown.
The object is at most 100mb in size at any given time, so there is no way that it is using all the desktop resources to load this object into memory, so I have been wondering whether it may be that Microsoft limits the amount of memory that an add in may use.
What I would like to know is of anyone knows if there is a size limit and what it may be, as well as how to increase it if there is a limit present?
Thank you in advance for any advice given.
UPDATE:
Here is the code of the class that I am serializing:
Imports System.Environment
Imports Microsoft.Win32.SafeHandles
Imports System.Runtime.InteropServices
<Serializable()> _
Public Class LocalDBObject
Private aOfficesDS As DataSet = New DataSet()
Private aFieldDS As DataSet = New DataSet()
Private aSectorsDS As DataSet = New DataSet()
Private aDocumentsDS As DataSet = New DataSet()
Private aLibraryDS As DataSet = New DataSet()
Private aRolesDS As DataSet = New DataSet()
Private aSettings As mySettings = New mySettings()
Private aUpdateDate As DateTime = DateTime.Now
Private aUser As UserInfo = New UserInfo()
Private aDistributionFilesDS As DataSet = New DataSet()
Public Property UpdateDate() As DateTime
Get
UpdateDate = aUpdateDate
End Get
Set(ByVal Value As DateTime)
aUpdateDate = Value
End Set
End Property
Public Property Settings() As mySettings
Get
Settings = aSettings
End Get
Set(ByVal Value As mySettings)
aSettings = Value
End Set
End Property
Public Property RolesDS() As DataSet
Get
RolesDS = aRolesDS
End Get
Set(ByVal Value As DataSet)
aRolesDS = Value
End Set
End Property
Public Property UserInfo() As UserInfo
Get
UserInfo = aUser
End Get
Set(ByVal Value As UserInfo)
aUser = Value
End Set
End Property
Public Shared Userfolder As String = GetFolderPath(SpecialFolder.ApplicationData) + "\CIM\" + Environment.UserName
Public Shared UserDistributionfolder As String = GetFolderPath(SpecialFolder.ApplicationData) + "\CIM\CIM Distribution Files"
Public Shared Function CheckFile() As Boolean
Return System.IO.File.Exists(Userfolder + "\LocalDB.dat")
End Function
Public Shared Sub Write(ByVal obj As LocalDBObject)
Serializer.Serialize2(obj, Userfolder + "\LocalDB.dat")
End Sub
Public Shared Function Read() As LocalDBObject
If Not System.IO.Directory.Exists(Userfolder) Then
System.IO.Directory.CreateDirectory(Userfolder)
End If
Dim obj As LocalDBObject = Serializer.deSerialize2(Userfolder + "\LocalDB.dat")
Return obj
End Function
Public Property DocumentsDS() As DataSet
Get
DocumentsDS = aDocumentsDS
End Get
Set(ByVal Value As DataSet)
aDocumentsDS = Value
End Set
End Property
Public Property LibraryDS() As DataSet
Get
LibraryDS = aLibraryDS
End Get
Set(ByVal Value As DataSet)
aLibraryDS = Value
End Set
End Property
Public Property OfficesDS() As DataSet
Get
OfficesDS = aOfficesDS
End Get
Set(ByVal Value As DataSet)
aOfficesDS = Value
End Set
End Property
Public Property FieldDS() As DataSet
Get
FieldDS = aFieldDS
End Get
Set(ByVal Value As DataSet)
aFieldDS = Value
End Set
End Property
Public Property SectorsDS() As DataSet
Get
SectorsDS = aSectorsDS
End Get
Set(ByVal Value As DataSet)
aSectorsDS = Value
End Set
End Property
Public Property DistributionDS() As DataSet
Get
DistributionDS = aDistributionFilesDS
End Get
Set(ByVal Value As DataSet)
aDistributionFilesDS = Value
End Set
End Property
Public Shared Function GetNameForLibaryGroup(ByVal FieldID As Integer, ByVal obj As LocalDBObject) As String
For Each dr As DataRow In obj.aFieldDS.Tables(0).Rows
If dr("FieldID") = FieldID Then
Return dr("FieldName")
End If
Next
Return ""
End Function
Public Shared Function GetFileForTemplate(ByVal DocID As Integer) As Byte()
Dim obj As CIMShared.LocalDBObject = CIMShared.LocalDBObject.Read()
For Each dr As DataRow In obj.DocumentsDS.Tables(0).Rows
If dr("docid") = DocID Then
Try
Dim data As Byte() = CType(dr("docdata"), Byte())
Return data
Catch ex As Exception
Return Nothing
End Try
End If
Next
Return Nothing
End Function
Public Shared Function GetFilenameForTemplate(ByVal DocID As Integer) As String
Dim obj As CIMShared.LocalDBObject = CIMShared.LocalDBObject.Read()
For Each dr As DataRow In obj.DocumentsDS.Tables(0).Rows()
If dr("docid") = DocID Then
Return Convert.ToString(LocalDBObject.Userfolder + "\" + dr("docName")) + "_" + Convert.ToString(dr("DocID")) + "." + Convert.ToString(dr("docext")).Substring(1)
End If
Next
Return Guid.NewGuid().ToString().Replace("-", "") + ".txt"
End Function
Public Shared Function GetFilenameOnlyForTemplate(ByVal DocID As Integer) As String
Dim obj As CIMShared.LocalDBObject = CIMShared.LocalDBObject.Read()
For Each dr As DataRow In obj.DocumentsDS.Tables(0).Rows()
If dr("docid") = DocID Then
Return Convert.ToString(dr("docName")) + "." + Convert.ToString(dr("docext")).Substring(1)
End If
Next
Return Guid.NewGuid().ToString().Replace("-", "") + ".txt"
End Function
Public Shared Function GetFilenameForPicture(ByVal DocID As Integer) As String
Dim obj As CIMShared.LocalDBObject = CIMShared.LocalDBObject.Read()
For Each dr As DataRow In obj.DocumentsDS.Tables(0).Rows()
If dr("docid") = DocID Then
Return Convert.ToString(LocalDBObject.Userfolder + "\" + dr("docName")) + "." + Convert.ToString(dr("docext")).Substring(1)
End If
Next
Return Guid.NewGuid().ToString().Replace("-", "") + ".txt"
End Function
Public Shared Function GetFileForLibrary(ByVal DocID As Integer) As Byte()
Dim obj As CIMShared.LocalDBObject = CIMShared.LocalDBObject.Read()
For Each dr As DataRow In obj.LibraryDS.Tables(0).Rows
If dr("docid") = DocID Then
Try
Dim data As Byte() = CType(dr("docdata"), Byte())
Return data
Catch ex As Exception
Return Nothing
End Try
End If
Next
Return Nothing
End Function
Public Shared Function GetFileLibaryDate(ByVal DocID As Integer) As DateTime
Dim obj As CIMShared.LocalDBObject = CIMShared.LocalDBObject.Read()
For Each dr As DataRow In obj.LibraryDS.Tables(0).Rows
If dr("docid") = DocID Then
Try
Dim adate As DateTime = Convert.ToDateTime(dr("docdateupdated"))
Return adate
Catch ex As Exception
Return DateTime.Now.AddYears(-100)
End Try
End If
Next
Return DateTime.Now.AddYears(-100)
End Function
Public Shared Function GetFilenameForLibary(ByVal DocID As Integer) As String
Dim obj As CIMShared.LocalDBObject = CIMShared.LocalDBObject.Read()
For Each dr As DataRow In obj.LibraryDS.Tables(0).Rows
If dr("docid") = DocID Then
Return Convert.ToString(LocalDBObject.Userfolder + "\" + dr("docName")) + "_" + Convert.ToString(dr("DocID")) + "." + Convert.ToString(dr("docext")).Substring(1)
End If
Next
Return Guid.NewGuid().ToString().Replace("-", "") + ".txt"
End Function
'EUGENE: Added this to get the distribution folders.
Public Shared Function GetDistributionFileDS() As List(Of Integer)
Dim LocalDocIDList As New List(Of Integer)
Dim obj As CIMShared.LocalDBObject = CIMShared.LocalDBObject.Read()
If obj.aDistributionFilesDS.Tables.Count > 0 Then
For Each Row As DataRow In obj.aDistributionFilesDS.Tables(0).Rows
LocalDocIDList.Add(Row("docid"))
Next
End If
Return LocalDocIDList
End Function
Public Shared Function GetDistributionFilePath(DocumentID As Integer) As String
Dim LocalDocumentPath As String = ""
Dim obj As CIMShared.LocalDBObject = CIMShared.LocalDBObject.Read()
For Each Row As DataRow In obj.aDistributionFilesDS.Tables(0).Rows
If Row("docid") = DocumentID Then
LocalDocumentPath = LocalDBObject.UserDistributionfolder + "\" + CStr(Row("docid")) + "-" + CStr(Row("docName")) + CStr(Row("docext"))
End If
Next
Return LocalDocumentPath
End Function
Public Shared Function GetDistributionFileData(DocumentID As Integer) As Byte()
Dim LocalDocumentData As Byte() = Nothing
Dim obj As CIMShared.LocalDBObject = CIMShared.LocalDBObject.Read()
For Each Row As DataRow In obj.aDistributionFilesDS.Tables(0).Rows
If Row("docid") = DocumentID Then
LocalDocumentData = CType(Row("docdata"), Byte())
End If
Next
Return LocalDocumentData
End Function
End Class
Here are the serializer functions that serializes the class, and that deserilizes the class.
Public Shared Sub Serialize(ByVal obj As LocalDBObject, ByVal FileName As String)
Dim Stream As New FileStream(FileName, FileMode.OpenOrCreate, FileAccess.Write, FileShare.ReadWrite)
Dim objStreamWriter As New StreamWriter(Stream)
Dim x As New XmlSerializer(obj.GetType)
x.Serialize(objStreamWriter, obj)
objStreamWriter.Close()
End Sub
Public Shared Function deSerialize(ByVal FileName As String) As LocalDBObject
Dim obj As New LocalDBObject()
Dim Stream As FileStream
Dim objStreamReader As StreamReader
Try
Stream = New FileStream(FileName, FileMode.Open, FileAccess.Read, FileShare.ReadWrite)
objStreamReader = New StreamReader(Stream)
Dim x As New XmlSerializer(obj.GetType)
obj = x.Deserialize(objStreamReader)
objStreamReader.Close()
Catch ex As Exception
obj = New LocalDBObject()
Try
Stream.Close()
Catch
End Try
Try
objStreamReader.Close()
Catch
End Try
End Try
Return obj
End Function
NOTE: I realize this is not the cleanest or neatest code, this is a former colleagues code that I am using and trying to resolve bugs on.
What is currently happening is that every time I de-serialize the class, which is about 300MB in size, I get a Out Of Memory Exception. In no way is this using all the computer memory, hence why I would like to find out if there is a memory usage limit on Microsoft Office add-ins?

Answer 1

What object are you talking about? Could you be more specific?
Anyway, I always suggest releasing underlying COM objects insteatly. Use System.Runtime.InteropServices.Marshal.ReleaseComObject to release an Office object when you have finished using it. Then set a variable to Nothing in Visual Basic (null in C#) to release the reference to the object. Read more about that in the Systematically Releasing Objects article.