Export to Excel From Datagridview

hi, I'm new to Vb.net and I need a little help. I have this Code to Export All Data from Datagridview to Excel and it works well, Problem 1 :

But what I want to do is To export only Specific columns, not all columns from Datagridview (Example I want to Export only Column 3 and 5) Not all Columns.

And Problem 2:
is It is possible to export in an existing template example I have an excel template with Name And ID to export in this existing template not in new.

Thank You.

Code:

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  ' Creating a Excel object.
        Dim excel As Microsoft.Office.Interop.Excel._Application = New Microsoft.Office.Interop.Excel.Application()
        Dim workbook As Microsoft.Office.Interop.Excel._Workbook = excel.Workbooks.Add(Type.Missing)
        Dim worksheet As Microsoft.Office.Interop.Excel._Worksheet = Nothing

        Try
            worksheet = workbook.ActiveSheet

            'worksheet.Name = "ExportedFromDatGrid" '
            worksheet.Name = Me.Text '
            Dim cellRowIndex As Integer = 1
            Dim cellColumnIndex As Integer = 1

            'Loop through each row and read value from each column.
            For i As Integer = -1 To dgw.Rows.Count - 1
                For j As Integer = 0 To dgw.Columns.Count - 1
                    ' Excel index starts from 1,1. As first Row would have the Column headers, adding a condition check.
                    If cellRowIndex = 1 Then
                        worksheet.Cells(cellRowIndex, cellColumnIndex) = dgw.Columns(j).HeaderText
                    Else
                        worksheet.Cells(cellRowIndex, cellColumnIndex) = dgw.Rows(i).Cells(j).Value.ToString()
                    End If
                    cellColumnIndex += 1
                Next
                cellColumnIndex = 1
                cellRowIndex += 1
            Next

            'Getting the location and file name of the excel to save from user.
            Dim saveDialog As New SaveFileDialog()
            saveDialog.Filter = "Excel files (*.xlsx)|*.xlsx|All files (*.*)|*.*"
            saveDialog.FilterIndex = 2

            If saveDialog.ShowDialog() = System.Windows.Forms.DialogResult.OK Then
                workbook.SaveAs(saveDialog.FileName)
                MsgBox("Export Successful", vbInformation)
            End If
        Catch ex As System.Exception
            MessageBox.Show(ex.Message) 'e paraqet probleim ne mesazh
        Finally
            excel.Quit()
            workbook = Nothing
            excel = Nothing
        End Try

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This is simple to export columns in a DataGridView when using the DataSource of the DataGridView with a DataTable using SpreadSheetLight via NuGet.

To get only needed columns, Crate a new DataTable as follows where you replace C1, C2 etc with column names from your DataTable

Code:

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Dim view As New DataView(dataTableFromDataGridView)
Dim selected As DataTable = view.ToTable("Selected", False, "C1", "C2")

---

Simple export code

Code:

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Public Shared Sub ExportTable(pFileName As String, pSheetName As String, pDataTable As DataTable, pColumnHeaders As Boolean)

    Using doc As New SLDocument()
        doc.SelectWorksheet(pSheetName)
        doc.ImportDataTable(1, SLConvert.ToColumnIndex("A"), pDataTable, pColumnHeaders)
        doc.RenameWorksheet(SLDocument.DefaultFirstSheetName, pSheetName)
        doc.SaveAs(pFileName)
    End Using

End Sub

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Styling can be done via SpreadSheetLight's SLStyle class e.g.

Code:

---

Using doc As New SLDocument(pFileName)

    doc.SelectWorksheet(pSheetName)
    doc.ImportDataTable(pStartRow, SLConvert.ToColumnIndex("A"), pDataTable, pColumnHeaders)

    Dim style As New SLStyle With {.FormatCode = "MM/dd//yyyy"}


    If pDataTable.Columns.Contains("ModifiedDate") Then
        doc.SetColumnStyle(pDataTable.Columns("ModifiedDate").Ordinal + 1, style)
    End If

    doc.Save()

    Return True

End Using

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