How do I fix "Public member 'Length' on type 'DBNull' not found" Excel Import Error in .NET?

Posted on 2008-10-21
Last Modified: 2011-10-19
How do I fix "Public member 'Length' on type 'DBNull' not found" Excel Import Error in .NET?
I have attached the file I am attempting to import and the code behind.  The code works, I have successfully used it on another file, but why not this one?

Any help is greatly appreciated.

What am I missing?
Partial Class crc_importcertificates

    Inherits System.Web.UI.Page

    Protected Sub btImport_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btImport.Click

        If FileUpload.HasFile Then

            Dim strFileName As String = ""

            Dim oleDbCommand As New Data.OleDb.OleDbCommand

            Dim oleDbReader As Data.OleDb.OleDbDataReader

            Dim sqlCommand As New Data.SqlClient.SqlCommand("crc_ImportCertificates", New Data.SqlClient.SqlConnection(ConfigurationManager.ConnectionStrings("cnDWS").ConnectionString))

            sqlCommand.CommandType = Data.CommandType.StoredProcedure

            'Save File to random filename


            strFileName = ConfigurationManager.AppSettings("FileUploadPath").ToString & CStr(Rnd()) & ".xls"

            If Not System.IO.File.Exists(strFileName) Then


            End If

            oleDbCommand.Connection = New Data.OleDb.OleDbConnection(Replace(ConfigurationManager.AppSettings("cnACT").ToString, "FILENAME", strFileName))

            oleDbCommand.CommandText = "SELECT * FROM [ExportCertificateData$];"



            oleDbReader = oleDbCommand.ExecuteReader

            sqlCommand.Parameters.Add("@first_name", Data.SqlDbType.VarChar)

            sqlCommand.Parameters.Add("@last_name", Data.SqlDbType.VarChar)

            sqlCommand.Parameters.Add("@address", Data.SqlDbType.VarChar)

            sqlCommand.Parameters.Add("@city", Data.SqlDbType.VarChar)

            sqlCommand.Parameters.Add("@state", Data.SqlDbType.VarChar)

            sqlCommand.Parameters.Add("@zip", Data.SqlDbType.VarChar)

            sqlCommand.Parameters.Add("@username", Data.SqlDbType.VarChar)

            sqlCommand.Parameters.Add("@password", Data.SqlDbType.VarChar)

            sqlCommand.Parameters.Add("@certificate_level", Data.SqlDbType.VarChar)

            sqlCommand.Parameters.Add("@mathematics_level", Data.SqlDbType.TinyInt)

            sqlCommand.Parameters.Add("@mathematics_tested", Data.SqlDbType.DateTime)

            sqlCommand.Parameters.Add("@reading_level", Data.SqlDbType.TinyInt)

            sqlCommand.Parameters.Add("@reading_tested", Data.SqlDbType.DateTime)

            sqlCommand.Parameters.Add("@locating_level", Data.SqlDbType.TinyInt)

            sqlCommand.Parameters.Add("@locating_tested", Data.SqlDbType.DateTime)

            sqlCommand.Parameters.Add("@certificate_issued", Data.SqlDbType.DateTime)

            sqlCommand.Parameters.Add("@expiration", Data.SqlDbType.DateTime)

            sqlCommand.Parameters.Add("@testing_location", Data.SqlDbType.VarChar)

            sqlCommand.Parameters.Add("@act_certificate_number", Data.SqlDbType.VarChar)

            'loop through records and update crc_certificates based on results

            While oleDbReader.Read()

                sqlCommand.Parameters("@first_name").Value = IIf(oleDbReader("First Name").Length = 0, System.DBNull.Value, oleDbReader("First Name"))

                sqlCommand.Parameters("@last_name").Value = IIf(oleDbReader("Last Name").Length = 0, System.DBNull.Value, oleDbReader("Last Name"))

                sqlCommand.Parameters("@address").Value = IIf(oleDbReader("Primary Address1").Length = 0, System.DBNull.Value, oleDbReader("Primary Address1"))

                sqlCommand.Parameters("@address").Value &= IIf(oleDbReader("Primary Address2").Length = 0, System.DBNull.Value, oleDbReader("Primary Address2"))

                sqlCommand.Parameters("@address").Value &= IIf(oleDbReader("Primary Address3").Length = 0, System.DBNull.Value, oleDbReader("Primary Address3"))

                sqlCommand.Parameters("@city").Value = IIf(oleDbReader("Primary City").Length = 0, System.DBNull.Value, oleDbReader("Primary City"))

                sqlCommand.Parameters("@state").Value = IIf(oleDbReader("Primary State").Length = 0, System.DBNull.Value, oleDbReader("Primary State"))

                sqlCommand.Parameters("@zip").Value = IIf(oleDbReader("Primary PostalCode/ZipCode").Length = 0, System.DBNull.Value, oleDbReader("Primary PostalCode/ZipCode"))

                sqlCommand.Parameters("@username").Value = oleDbReader("MyWorkKeys UserName")

                sqlCommand.Parameters("@password").Value = oleDbReader("Password")

                sqlCommand.Parameters("@certificate_level").Value = oleDbReader("Certificate Level")

                sqlCommand.Parameters("@mathematics_level").Value = oleDbReader("Applied Mathematics Score")

                sqlCommand.Parameters("@mathematics_tested").Value = oleDbReader("Applied Mathematics Test Date")

                sqlCommand.Parameters("@reading_level").Value = oleDbReader("Reading for Information Score")

                sqlCommand.Parameters("@reading_tested").Value = oleDbReader("Reading for Information Test Date")

                sqlCommand.Parameters("@locating_level").Value = oleDbReader("Locating Information Score")

                sqlCommand.Parameters("@locating_tested").Value = oleDbReader("Locating Information Test Date")

                sqlCommand.Parameters("@certificate_issued").Value = oleDbReader("Certificate Issue Date")

                sqlCommand.Parameters("@expiration").Value = oleDbReader("Certificate Expiration Date")

                sqlCommand.Parameters("@testing_location").Value = oleDbReader("Last Known Testing Location")

                sqlCommand.Parameters("@act_certificate_number").Value = oleDbReader("Certificate Identifier")


            End While



            'clean up


            lblStatus.Visible = True

        End If

    End Sub

    Protected Sub btReturn_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btReturn.Click

        Response.Redirect("default.aspx", True)

    End Sub

End Class

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Question by:devnewbee
1 Comment
LVL 18

Accepted Solution

UnifiedIS earned 500 total points
ID: 22769483
You can also usually just bypass the null checks with empty strings
sqlCommand.Parameters("@address") = string.empty & oleDbReader("Primary Address1")

Another way would be to reverse your iiif logic
if isdbnull(oledbreader(fieldname)) then dbnull.value else oledbreader(fieldname)


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