Multithreaded application - access to method's objects

Hi All,

I'm new in multithreaded programming and I'd like to ask you for help.
I want to develop application which needs to execute reports. I have to use multithreading functionality because execution one of the report can take a lot of time and others can't wait for process to finish.
I'm using external dll to connect to datasource, create session for specified project and then to execute report.

Below is the code I'm using:

In the loop I create and start thread with passed object.

Code:

Sub Main()

        Dim arr(2) As String

        Dim arrD(2) As String



        arr(1) = "0A9EBE87468B751C3663818889B10D73" 

        arr(2) = "8AC5B5784154EBD2D585C38BF7F7E673"



        arrD(2) = "Project1"

        arrD(1) = "Project2"



       For i = 1 To 2

            Dim myThread As New Threading.Thread(AddressOf RefreshCube)



            Dim obj = New CubeData()

            obj.ID = arr(i)

            obj.DataSourceName = "192.168.0.11"

            obj.login = "administrator"

            obj.pwd = ""

            obj.ProjectName = arrD(i)



            myThread.Start(obj)

        Next

End sub

The problem occurs in RefreshCube method.
When first thread tries to init DataSource than I get message that Data Source can't be initialized. I think it's because the second thread in the meantime execute the same method and creates new object of DataSource and the first thread tries to initialize empty object.

Code:

Sub RefreshCube(Cube As CubeData)

Dim DataSource As DSSDataSource

dim retVal as String



     Try

            DataSource = New DSSDataSource()

            DataSource.Type = EnumDSSDataSourceType.DssDataSourceTypeServer

            DataSource.Location = Cube.DataSourceName

            DataSource.Mode = EnumDSSConnectionMode.DssConnectionModeServerAccess



            DataSource.AuthMode = EnumDSSAuthModes.DssAuthStandard

            DataSource.login = Cube.login

            DataSource.Passwd = Cube.pwd

            DataSource.Init() '<-- problem appears when thread tries to Init Datasorce



           'code for creating session and executing report

               ................................................



        Catch ex As Exception

            retVal = ex.Message

            Console.WriteLine(ex.Message)

        End Try

End Sub

The question is how I can make my code to execute reports asynchronusly without this conflict?

Thanks,
Lukasz

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