I know this is late, but I had the same issue.
I used to use Microsoft.Office.Interop.Excel
to export data to an xlsx
file without saving it. It would present itself nicely as Book1.xlsx to the end-user who could them save it or close it without saving as required.
I have also moved to EPPlus to improve the speed of my exports and therefore, as you have experienced, cannot present the open file to the end-user without it first being saved.
The approach I have taken, using the SaveFileDialog component is to prompt the user for a name before the EPPlus
file is created. This at least allows the end-user to identify where the file should be saved, rather than using a 'hard-coded' directory.
Private Sub btnExportXlsxEPPlus_Click(sender As Object, e As EventArgs) Handles btnExportXlsxEPPlus.Click
Try
Dim filInf As FileInfo = New FileInfo(GetFileToSave())
Using excelPackage As ExcelPackage = New ExcelPackage
excelPackage.Workbook.Properties.Author = "enLIGHTen"
excelPackage.Workbook.Properties.Title = "enLIGHTen Report"
excelPackage.Workbook.Properties.Subject = "enLIGHTen export data"
excelPackage.Workbook.Properties.Created = Date.Now
Dim worksheet As ExcelWorksheet = excelPackage.Workbook.Worksheets.Add("Sheet 1")
worksheet.Cells("A1").Value = "My EPPlus spreadsheet!"
worksheet.Cells(1, 2).Value = "This is cell B1!"
excelPackage.SaveAs(filInf)
End Using
Using excelPackage As ExcelPackage = New ExcelPackage(filInf)
Dim firstWorksheet As ExcelWorksheet = excelPackage.Workbook.Worksheets(1)
Dim namedWorksheet As ExcelWorksheet = excelPackage.Workbook.Worksheets("SomeWorksheet")
Dim anotherWorksheet As ExcelWorksheet = excelPackage.Workbook.Worksheets.FirstOrDefault(Function(x) x.Name Is "SomeWorksheet")
Dim valA1 As String = firstWorksheet.Cells("A1").Value.ToString
Dim valB1 As String = firstWorksheet.Cells(1, 2).Value.ToString
excelPackage.Save()
End Using
Dim proc As Process
Try
proc = New Process()
Process.Start(filInf.FullName)
Catch ex As Exception
MsgBox("File cannot be opened", MsgBoxStyle.Information, "Cannot open file")
End Try
Catch
End Try
End Sub
Public Function GetFileToSave()
Dim strFilename As String = ""
SaveFileDialog1.Filter = "Excel Workbook (*.xlsx)|*.xlsx"
If SaveFileDialog1.ShowDialog = Windows.Forms.DialogResult.OK Then
strFilename = SaveFileDialog1.FileName
Return strFilename
End If
End Function