私はVisual Basic.netでDataGridViewをPdfに印刷しようとしています。NullReferenceExceptionが発生しても処理できませんでした。私は助けてください。Visual Basic DataGridViewからPDF例外例外エラー
Private Sub Button5_Click(sender As Object, e As EventArgs) Handles Button5.Click
'Creating iTextSharp Table from the DataTable data
Dim pdfTable As New PdfPTable(DataGridView1.ColumnCount)
pdfTable.DefaultCell.Padding = 3
pdfTable.WidthPercentage = 30
pdfTable.HorizontalAlignment = Element.ALIGN_LEFT
pdfTable.DefaultCell.BorderWidth = 1
'Adding Header row
For Each column As DataGridViewColumn In DataGridView1.Columns
Dim cell As New PdfPCell(New Phrase(column.HeaderText))
cell.BackgroundColor = New iTextSharp.text.BaseColor(240, 240, 240)
pdfTable.AddCell(cell)
Next
'Adding DataRow
For Each row As DataGridViewRow In DataGridView1.Rows
For Each cell As DataGridViewCell In row.Cells
**pdfTable.AddCell(cell.Value.ToString())** (this is where the exception is thrown)
Next
Next
'Exporting to PDF
Dim folderPath As String = "C:\Users\mnevi\Documents\testpdf"
If Not Directory.Exists(folderPath) Then
Directory.CreateDirectory(folderPath)
End If
Using stream As New FileStream(folderPath & "DataGridViewExport.pdf", FileMode.Create)
Dim pdfDoc As New Document(PageSize.A2, 10.0F, 10.0F, 10.0F, 0.0F)
PdfWriter.GetInstance(pdfDoc, stream)
pdfDoc.Open()
pdfDoc.Add(pdfTable)
pdfDoc.Close()
stream.Close()
End Using
End Sub
私は上記の例外を**で投げているコードに**を付けました。どんな支援も大歓迎です。
[NullReferenceExceptionとは何か、それを修正するにはどうすればいいですか?](http://stackoverflow.com/questions/4660142/what-is-a-nullreferenceexception-and-how-do-i-fix -it) – Blackwood