vb.net can't get database value in OR statement - sql

Question

i have kriteria database with column name kode which contain value kriteria 1 to kriteria 6
I want user can pick 3 to 6 value from kode and it will show in datagridview as matrix...
if user pick 6 kriteria there's no problem and it show matrix 6x6
...but if user pick less than 6 kriteria or parameters empty, it shows nothing...
this is my code
Private Sub perhitungankriteria_Load(sender As Object, e As EventArgs) Handles MyBase.Load
For Each item In menuuser.ListBox2.Items
list2.Add(item)
Next
connect()
End Sub
Sub connect()
Dim adapter As OleDbDataReader
Dim cmd As OleDbCommand
cmd = New OleDbCommand("SELECT kode FROM kriteria WHERE kode=#kriteria1 OR kode=#kriteria2 OR kode=#kriteria3 OR kode=#kriteria4 OR kode=#kriteria5 OR kode=#kriteria6", konek)
cmd.Parameters.Add("#kriteria1", OleDbType.VarChar, 50).Value = list2(0)
cmd.Parameters.Add("#kriteria2", OleDbType.VarChar, 50).Value = list2(1)
cmd.Parameters.Add("#kriteria3", OleDbType.VarChar, 50).Value = list2(2)
cmd.Parameters.Add("#kriteria4", OleDbType.VarChar, 50).Value = list2(3)
cmd.Parameters.Add("#kriteria5", OleDbType.VarChar, 50).Value = list2(4)
cmd.Parameters.Add("#kriteria6", OleDbType.VarChar, 50).Value = list2(5)
adapter = cmd.ExecuteReader
DataGridView1.Columns.Clear()
While adapter.Read
list.Add(adapter("kode"))
DataGridView1.Columns.Add(adapter("kode"), adapter("kode"))
End While
i've try IN instead WHERE query in sql SELECT statement but same problems appears

Answer 1

Call BuildCommand from a button click after the user has made selections from the list box.
Dim list2() As String = {"kriteria1", "kriteria2", "kriteria3", "kriteria4", "kriteria5", "kriteria6"}
Private Sub Form4_Load(sender As Object, e As EventArgs) Handles MyBase.Load
ListBox1.DataSource = list2
Private Sub BuildCommand()
Dim sb As New StringBuilder("SELECT kode FROM kriteria WHERE kode = ")
Dim ct As Integer = ListBox1.SelectedItems.Count
Dim cn As New OleDbConnection("Your connection string")
Dim cmd As New OleDbCommand
cmd.Parameters.Add("#kriteria1", OleDbType.VarChar, 50).Value = list2(0)
cmd.Parameters.Add("#kriteria2", OleDbType.VarChar, 50).Value = list2(1)
cmd.Parameters.Add("#kriteria3", OleDbType.VarChar, 50).Value = list2(2)
cmd.Parameters.Add("#kriteria4", OleDbType.VarChar, 50).Value = list2(3)
cmd.Parameters.Add("#kriteria5", OleDbType.VarChar, 50).Value = list2(4)
cmd.Parameters.Add("#kriteria6", OleDbType.VarChar, 50).Value = list2(5)
If ListBox1.SelectedItems.Contains(ListBox1.Items(0)) Then
sb.Append("#kriteria1 OR kode = ")
End If
If ListBox1.SelectedItems.Contains(ListBox1.Items(1)) Then
sb.Append("#kriteria2 OR kode = ")
End If
If ListBox1.SelectedItems.Contains(ListBox1.Items(2)) Then
sb.Append("#kriteria3 OR kode = ")
End If
If ListBox1.SelectedItems.Contains(ListBox1.Items(3)) Then
sb.Append("#kriteria4 OR kode = ")
End If
If ListBox1.SelectedItems.Contains(ListBox1.Items(4)) Then
sb.Append("#kriteria5 OR kode = ")
End If
If ListBox1.SelectedItems.Contains(ListBox1.Items(5)) Then
sb.Append("#kriteria6;")
End If
Dim strSQL As String = sb.ToString
If strSQL.EndsWith("= ") Then
Dim index As Integer = strSQL.LastIndexOf("O") 'last capital O
strSQL = strSQL.Remove(index)
strSQL &= ";"
End If
Debug.Print(strSQL) 'Check the immediate window
cmd.CommandText = strSQL
cmd.Connection = cn
'use your command as you wish
End Sub