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

Open in new window

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)


Featured Post

3 Use Cases for Connected Systems

Our Dev teams are like yours. They’re continually cranking out code for new features/bugs fixes, testing, deploying, testing some more, responding to production monitoring events and more. It’s complex. So, we thought you’d like to see what’s working for us.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

The debugging module of the VB 6 IDE can be accessed by way of the Debug menu item. That menu item can normally be found in the IDE's main menu line as shown in this picture.   There is also a companion Debug Toolbar that looks like the followin…
Calculating holidays and working days is a function that is often needed yet it is not one found within the Framework. This article presents one approach to building a working-day calculator for use in .NET.
Get people started with the utilization of class modules. Class modules can be a powerful tool in Microsoft Access. They allow you to create self-contained objects that encapsulate functionality. They can easily hide the complexity of a process from…
Show developers how to use a criteria form to limit the data that appears on an Access report. It is a common requirement that users can specify the criteria for a report at runtime. The easiest way to accomplish this is using a criteria form that a…

786 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question