Generating PDf from Multiple Excel sheet using VB.net

Question

CAn any one please provide me the solution for
 
Generating PDf from Multiple Excel sheet using VB.net
 
I am using below code nut it is not working:
 
' Dim fileName As String = AppDomain.CurrentDomain.BaseDirectory & "WeeklyReport"
' Dim xlsApp = New Microsoft.Office.Interop.Excel.Application
' xlsApp.ScreenUpdating = False
' Dim xlsBook As Microsoft.Office.Interop.Excel.Workbook
' Dim paramOpenAfterPublish As Boolean = False
' Dim paramIncludeDocProps As Boolean = True
' Dim paramIgnorePrintAreas As Boolean = True
' Dim paramFromPage As Object = Type.Missing
' Dim paramToPage As Object = Type.Missing
' xlsBook = xlsApp.Workbooks.Open(fileName & ".xls", UpdateLinks:=False, ReadOnly:=False)
 
' ' xlsBook.ExportAsFixedFormat(Microsoft.Office.Interop.Excel.XlFixedFormatType.xlTypePDF, fileName & ".pdf", Microsoft.Office.Interop.Excel.XlFixedFormatQuality.xlQualityStandard, paramIncludeDocProps, paramIgnorePrintAreas, paramFromPage, paramToPage, paramOpenAfterPublish)
' xlsBook.ExportAsFixedFormat(Microsoft.Office.Interop.Excel.XlFixedFormatType.xlTypePDF, fileName & ".pdf", Microsoft.Office.Interop.Excel.XlFixedFormatQuality.xlQualityStandard, Type.Missing, False, Type.Missing, Type.Missing, False, Type.Missing)
' xlsBook.Close(SaveChanges:=False)
' xlsApp.Quit()