[VB 2010] InvalidCastException was unhandled by user code

iboumiza · December 10th, 2011, 11:16 AM

Hi,

I use this code to populate combobox1&2:

Code:

 
'Main form on load events
    Private Sub frm_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load

        'Connect to Access Database
        dbProvider = "Provider=Microsoft.Jet.OLEDB.4.0;"
        dbSource = "Data Source = C:\DB.mdb;Jet OLEDB:Database Password=Pass;"
        con.ConnectionString = dbProvider & dbSource
        con.Open()

        'Call populate combobox procedure
        popCbo1()
        popCbo2()
        popCbo3()

    End Sub

    Private Sub popCbo1()
        sql1 = "SELECT DISTINCT location FROM Table ORDER BY location ASC"
        da1 = New OleDb.OleDbDataAdapter(sql1, con)
        da1.Fill(ds1, "Tab1")
        popCbo1.DataSource = ds1.Tables(0)
        popCbo1.DisplayMember = "location"
        popCbo1.ValueMember = "location"
    End Sub
    
    Private Sub popCbo2()
        sql2 = "SELECT DISTINCT director FROM Table WHERE lcoation = '" & popCbo1.SelectedValue & "' ORDER BY director"
        da2 = New OleDb.OleDbDataAdapter(sql2, con)
        da2.Fill(ds2, "Tab2n")
        popCbo2.DataSource = ds2.Tables(0)
        popCbo2.DisplayMember = "director"
        popCbo2.ValueMember = "director"
    End Sub

and to cascade result:

Code:

   
Private Sub popCbo1_SelectedIndexChanged(sender As System.Object, e As System.EventArgs) Handles popCbo1.SelectedIndexChanged
        popCbo2()
    End Sub

    Private Sub popCbo1_SelectionChangeCommitted(sender As Object, e As System.EventArgs) Handles popCbo1.SelectionChangeCommitted
        popCbo2()
    End Sub

but in the end I receive this error message:

InvalidCastException was unhandled by user code

and points to:

Code:

sql2 = "SELECT DISTINCT director FROM Table WHERE lcoation = '" & popCbo1.SelectedValue & "' ORDER BY director"

How to fix this, please?

Regards