Convert .xlsx & .xls to .csv VB.NET

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With refernce to below mentioned solution I have converted code from C# to VB but now I am stuck in Object reference error please help so i can convert my excel to csv

What I have tried:

Convert .xlsx & .xls to .csv[^]

Dim Upath As String = "~/Uploads/" + CDate(Today.Date).ToString("yyyyMMdd")
Dim excelPath As String = Server.MapPath(Upath + "/BKP/") + Path.GetFileName(FileUpload1.PostedFile.FileName)
FileUpload1.SaveAs(excelPath)
Dim csvPath As String = Server.MapPath(Upath) + "/" + Path.GetFileNameWithoutExtension(FileUpload1.PostedFile.FileName) + ".csv"
Dim stream As FileStream = File.Open(excelPath, FileMode.Open, FileAccess.Read)
Dim excelReader As IExcelDataReader = ExcelReaderFactory.CreateBinaryReader(stream)
'Dim excelReader As IExcelDataReader = ExcelReaderFactory.CreateOpenXmlReader(stream)
excelReader.IsFirstRowAsColumnNames = True
Dim result As DataSet = excelReader.AsDataSet()
Dim csvdata As String = ""
Dim row_no As Integer = 0
Dim DT As DataTable
DT = result.Tables(0) ''HERE I AM OBJECT REFERENCE ERROR
GridView1.DataSource = DT
excelReader.Close()

Posted 13-Apr-20 7:16am

Hemil Gandhi

Updated 12-May-23 4:10am

v2

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2 solutions

Solution 2

Dim DT As New DataTable

Try this, perhaps it helps.

Posted 12-May-23 4:10am

halovalo

Comments

Richard Deeming 12-May-23 10:15am

Read the question again:

Dim DT As DataTable
DT = result.Tables(0) ''HERE I AM OBJECT REFERENCE ERROR

The DT variable is assigned on the line immediately after it is declared. Setting it to a new DataTable instance only to immediately throw that instance away isn't going to help.

The problem is clearly that either result is Nothing, or it doesn't contain any tables.

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Richard MacCutchan · Accepted Answer · 2020-04-13T21:35:00

Solution 1

Please post your question in the forum at the end of the article, so that author can help you.

Posted 13-Apr-20 21:35pm

Richard MacCutchan

Comments

Hemil Gandhi 14-Apr-20 11:27am

have already done that

Richard MacCutchan 14-Apr-20 11:51am

If you want anyone to help here you need to explain what your problem is.

Hemil Gandhi 14-Apr-20 12:06pm

question updated as i have tried multiple solutions , now i am stuck with object reference error.

Richard MacCutchan 14-Apr-20 12:23pm

You have declared result but not created any Tables inside it (I assume). So the reference Tables(0) is most likely null. You can check that with the debugger.

Hemil Gandhi 15-Apr-20 10:17am

Sir sorry to bother you but i am beginner, so i dont get your solution. please elaborate it.

Richard MacCutchan 15-Apr-20 10:51am

Dim result As DataSet = excelReader.AsDataSet() ' you create the variable result, but it does not refer to anything.
Dim csvdata As String = ""Dim row_no As Integer = 0
Dim DT As DataTableDT = result.Tables(0) ''HERE I AM OBJECT REFERENCE ERROR - because result does not point to any tables.