Question

I have an ms-access database called db.mdb and it contains various table. I;m creating a Account Creation page with ASP.NET and VB.NET.

I’m trying to input fields within the page into ms-acess db but when I open the db there are no values entered despite web develop not showing any errors.

Can you kindly help me?

This is the code:

Imports System.Data
Imports System.Data.OleDb
Imports System.Data.Odbc



Partial Class _Default
    Inherits System.Web.UI.Page

    Protected Sub TextBox1_TextChanged(sender As Object, e As System.EventArgs) Handles txtName.TextChanged

    End Sub

    Protected Sub btnCreateAccount_Click(sender As Object, e As System.EventArgs) Handles btnCreateAccount.Click

        Dim conn As New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\Users\Brian\Documents\Visual Studio 2010\WebSites\WebSite3\db.mdb;User Id=admin;Password=;")

        Dim cmd As OleDbCommand = New OleDbCommand("INSERT INTO [USER] (UserName, UserSurname, Address, Country, TelNo, UserLogin, UserPassword, UserTypeID) VALUES (?, ?, ?, ?, ?, ?, ?, ?)", conn)




        If txtPass.Text = txtCPass.Text Then

            conn.Open()


            cmd.Parameters.Add("@UserName", OleDbType.VarChar, 255).Value = txtName.Text
            cmd.Parameters.Add("@UserSurname", OleDbType.VarChar, 255).Value = txtSurname.Text
            cmd.Parameters.Add("@Address", OleDbType.VarChar, 255).Value = txtUsername.Text
            cmd.Parameters.Add("@Country", OleDbType.VarChar, 255).Value = txtCountry.Text
            cmd.Parameters.Add("@TelNo", OleDbType.Integer).Value = txtTelNo.Text
            cmd.Parameters.Add("@UserLogin", OleDbType.VarChar, 255).Value = txtUsername.Text
            cmd.Parameters.Add("@UserPassword", OleDbType.VarChar, 255).Value = txtPass.Text
            cmd.Parameters.Add("@UserTypeID", OleDbType.VarChar, 255).Value = "U"





            cmd.ExecuteNonQuery()

            conn.Close()
            lblAccount.Visible = True



        End If

    End Sub
End Class

EDIT:

So I’m trying to autonumber the UserID field. It’s set as auto number from the access database. Whenever I try to input the details into the page from the page, it won’t allow me, giving me an error that the AutoNumber field cannot be NULL. So I added the piece of code :

newID = Int32.Parse(cmd2.ExecuteScalar()) + 1

So that I get the maximum number from that column in the table and increment it by 1 and then added with the other command.

cmd.Parameters.Add("@UserID", OleDbType.VarChar, 255).Value = newID

However its giving me an error saying

Conversion from type 'DBNull' to type 'String' is not valid.

Answer 1

You haven’t open the connection before calling cmd2.ExecuteScalar() function. And first parameter is wrong. Should be @UserID instead of @Address.

conn.Open()
newID = Int32.Parse(cmd2.ExecuteScalar()) + 1
'Not sure what is column type (Varchar or Int)
cmd.Parameters.Add("@UserID", OleDbType.Integer, 2).Value = newID
...
cmd.ExecuteNonQuery()
conn.Close()