VB.NET error adding a record to database - vb.net

Question

I'm using the code from http://homeandlearn.co.uk/NET/nets12p9.html for adding a record to the database.
It says when using a commandbuilder I should not get the error message:
Update requires a valid InsertCommand when passed DataRow collection with new rows.
However when I do the update I still get the error message. How can I fix this?
This is my code:
Dim dbProv As String
Dim dbSource As String
Dim con As New OleDb.OleDbConnection
Dim ds As New DataSet
Dim da As New OleDb.OleDbDataAdapter
Dim sql As String
Dim Command As OleDb.OleDbCommand
Dim dr As DataRow
Dim cb As New OleDb.OleDbCommandBuilder(da)
sql = "SELECT * FROM Cliënten"
dbProv = "PROVIDER=Microsoft.Jet.OLEDB.4.0;"
dbSource = "Data Source = [mydatabase]"
con.ConnectionString = dbProv & dbSource
con.Open()
da = New OleDb.OleDbDataAdapter(sql, con)
da.Fill(ds, "Cliënten")
dr = ds.Tables("Cliënten").NewRow()
dr.Item("Field1") = TextBox1.Text
dr.Item("Field2") = TextBox2.Text
ds.Tables("Cliënten").Rows.Add(dr)
da.Update(ds, "Cliënten")
MsgBox("New Record added to the Database")
con.Close()

Answer 1

To make da.Update() works, you must assign a valid InsertCommand, then the DataAdapter will execute it automatically. Here an example:
da.InsertCommand = New OleDb.OleDbCommand("INTERT INTO Cliënten (Field1, Field2) VALUES (#field1, #field2)")
da.InsertCommand.Parameters.Add(New OleDb.OleDbParameter("#field1", OleDb.OleDbType.VarChar, 0, "Field1"))
da.InsertCommand.Parameters.Add(New OleDb.OleDbParameter("#field2", OleDb.OleDbType.VarChar, 0, "Field2"))
da.Update(ds, "Cliënten")
WARNING: I've presumed you are using OleDb.OleDbType.VarChar for Field1 and Field2; if not you have to replace it with correct DB data format.

Answer 2

From what I read here it seems as though CommandBuilder should auto-generate the INSERT command for you based on the SELECT.
I think you are creating your CommandBuilder object too early - ie Before you specify the SELECT command / initialise Connection etc.
Perhaps this may work better...
Dim dbProv As String
Dim dbSource As String
Dim con As New OleDb.OleDbConnection
Dim ds As New DataSet
Dim da As New OleDb.OleDbDataAdapter
Dim sql As String
Dim Command As OleDb.OleDbCommand
Dim dr As DataRow
sql = "SELECT * FROM Cliënten" 'Consider specifying columns
'individually rather than using *
dbProv = "PROVIDER=Microsoft.Jet.OLEDB.4.0;"
dbSource = "Data Source = [mydatabase]"
con.ConnectionString = dbProv & dbSource
con.Open()
da = New OleDb.OleDbDataAdapter(sql, con)
Dim cb As New OleDb.OleDbCommandBuilder(da) 'Init CommandBuilder here
cb.RefreshSchema() 'This may also help
da.Fill(ds, "Cliënten")
dr = ds.Tables("Cliënten").NewRow()
dr.Item("Field1") = TextBox1.Text
dr.Item("Field2") = TextBox2.Text
ds.Tables("Cliënten").Rows.Add(dr)
da.Update(ds, "Cliënten")
MsgBox("New Record added to the Database")
con.Close()