Exportation rapide de la Grande Table de données de feuille de calcul Excel dans VB.Net

J'ai une intéressante énigme ici, comment puis-je rapidement (moins de 1 minute) à l'exportation d'un grand datatable (rempli à partir de SQL, de 35 000 lignes) dans une feuille de calcul Excel pour les utilisateurs. Je code à la place que peut gérer l'exportation, et alors que rien n'est "mal" avec le code en soi, il est infuriatingly lente prise de 4 minutes pour exporter le fichier en entier (parfois plus si l'utilisateur a moins de RAM ou est en cours d'exécution plus sur leur système). Malheureusement, c'est une amélioration par rapport à l'10+ minutes il sert à prendre à l'aide de notre vieille méthode. Tout simplement, cela peut être fait plus rapidement, sans l'aide de la 3e partie des composants? Si oui, comment? Mon code est comme suit, le ralentissement se produit entre messageboxes 6 et 7, où chaque ligne est écrite. Merci à vous tous de prendre le temps de jeter un oeil à ceci:

    Private Sub btnTest_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnJeffTest.Click
Test(MySPtoExport)
End Sub
Private Sub Test(ByVal SQL As String)
'Declare variables used to execute the VUE Export stored procedure
MsgBox("start stop watch")
Dim ConnectionString As New SqlConnection(CType(ConfigurationManager.AppSettings("ConnString"), String))
Dim cmdSP As New SqlClient.SqlCommand
Dim MyParam As New SqlClient.SqlParameter
Dim MyDataAdapter As New SqlClient.SqlDataAdapter
Dim ExportDataSet As New DataTable
Dim FilePath As String
MsgBox("stop 1 - end of declare")
Try
' open the connection
ConnectionString.Open()
' Use the connection for this sql command
cmdSP.Connection = ConnectionString
'set this command as a stored procedure command
cmdSP.CommandType = CommandType.StoredProcedure
'get the stored procedure name and plug it in
cmdSP.CommandText = SQL
'Add the Start Date parameter if required
Select Case StDt
Case Nothing
' there's no parameter to add
Case Is = 0
' there's no parameter to add
Case Else
'add the parameter name, it's direction and its value
MyParam = cmdSP.Parameters.Add("@StartDate", SqlDbType.VarChar)
MyParam.Direction = ParameterDirection.Input
MyParam.Value = Me.txtStartDate.Text
End Select
MsgBox("stop 2 - sql ready")
'Add the End Date parameter if required
Select Case EdDt
Case Nothing
' there's no parameter to add
Case Is = 0
' there's no parameter to add
Case Else
'add the parameter name, it's direction and its value
MyParam = cmdSP.Parameters.Add("@EndDate", SqlDbType.VarChar)
MyParam.Direction = ParameterDirection.Input
MyParam.Value = Me.txtEndDate.Text
End Select
'Add the single parameter 1 parameter if required
Select Case SPar1
Case Is = Nothing
' there's no parameter to add
Case Is = ""
' there's no parameter to add
Case Else
'add the parameter name, it's direction and its value
MyParam = cmdSP.Parameters.Add(SPar1, SqlDbType.VarChar)
MyParam.Direction = ParameterDirection.Input
MyParam.Value = Me.txtSingleReportCrt1.Text
End Select
'Add the single parameter 2 parameter if required
Select Case Spar2
Case Is = Nothing
' there's no parameter to add
Case Is = ""
' there's no parameter to add
Case Else
'add the parameter name, it's direction and its value
MyParam = cmdSP.Parameters.Add(Spar2, SqlDbType.VarChar)
MyParam.Direction = ParameterDirection.Input
MyParam.Value = Me.txtSingleReportCrt2.Text
End Select
MsgBox("stop 3 - params ready")
'Prepare the data adapter with the selected command 
MyDataAdapter.SelectCommand = cmdSP
' Set the accept changes during fill to false for the NYPDA export
MyDataAdapter.AcceptChangesDuringFill = False
'Fill the Dataset tables (Table 0 = Exam Eligibilities, Table 1  = Candidates Demographics)
MyDataAdapter.Fill(ExportDataSet)
'Close the connection
ConnectionString.Close()
'refresh the destination path in case they changed it
SPDestination = txtPDFDestination.Text
MsgBox("stop 4 - procedure ran, datatable filled")
Select Case ExcelFile
Case True
FilePath = SPDestination & lblReportName.Text & ".xls"
Dim _excel As New Microsoft.Office.Interop.Excel.Application
Dim wBook As Microsoft.Office.Interop.Excel.Workbook
Dim wSheet As Microsoft.Office.Interop.Excel.Worksheet
wBook = _excel.Workbooks.Add()
wSheet = wBook.ActiveSheet()
Dim dt As System.Data.DataTable = ExportDataSet
Dim dc As System.Data.DataColumn
Dim dr As System.Data.DataRow
Dim colIndex As Integer = 0
Dim rowIndex As Integer = 0
MsgBox("stop 5 - excel stuff declared")
For Each dc In dt.Columns
colIndex = colIndex + 1
_excel.Cells(1, colIndex) = dc.ColumnName
Next
MsgBox("stop 6 - Header written")
For Each dr In dt.Rows
rowIndex = rowIndex + 1
colIndex = 0
For Each dc In dt.Columns
colIndex = colIndex + 1
_excel.Cells(rowIndex + 1, colIndex) = dr(dc.ColumnName)
Next
Next
MsgBox("stop 7 - rows written")
wSheet.Columns.AutoFit()
MsgBox("stop 8 - autofit complete")
Dim strFileName = SPDestination & lblReportName.Text & ".xls"
If System.IO.File.Exists(strFileName) Then
System.IO.File.Delete(strFileName)
End If
MsgBox("stop 9 - file checked")
wBook.SaveAs(strFileName)
wBook.Close()
_excel.Quit()
End Select
MsgBox("File " & lblReportName.Text & " Exported Successfully!")
'Dispose of unneeded objects
MyDataAdapter.Dispose()
ExportDataSet.Dispose()
StDt = Nothing
EdDt = Nothing
SPar1 = Nothing
Spar2 = Nothing
MyParam = Nothing
cmdSP.Dispose()
cmdSP = Nothing
MyDataAdapter = Nothing
ExportDataSet = Nothing
Catch ex As Exception
'  Something went terribly wrong.  Warn user.
MessageBox.Show("Error: " & ex.Message, "Stored Procedure Running Process ", _
MessageBoxButtons.OK, MessageBoxIcon.Error)
Finally
'close the connection in case is still open
If Not ConnectionString.State = ConnectionState.Closed Then
ConnectionString.Close()
ConnectionString = Nothing
End If
' reset the fields
ResetFields()
End Try
End Sub