Disable/Enable Controls (Textbox) in SplitContainer

[weirdguy]

Hello all,

Currently, I am building an Catalog Application where User can search, edit, add and delete Product_ID on a same form.

I am using Split Container (Vertical) to section out form's controls.
Panel1 (Top) contains Header of the Form, searchbar (plan - not constructed yet).
Panel2 (Bottom) has 1 DataGridView (Dock: Left) which display all Product_Item and connected to SQL Database.Also, 8 textboxes and label. Hence, whenever User clicked any row at DataGridView, extra data will be shown in the textboxes.

Question,
I would like a Loop to auto Disabled/Enabled these textboxes on form_load and a button_click.

I had tried:-

Dim ctl As Control
For Each ctl In Me.Panel2.Controls
     If TypeOf ctl Is TextBox Then
 
          ctl.Enabled = False
     End If
Next

I am not really sure why it does not work.

[weirdguy]

Problem Above solved!
I decided not to use Split Container and use TableLayoutPanel to section the Header and DataGridView. While my TextBoxes, they are located on the form as normal, without any Container.

However, a new problem popped-out when I trying to update my data.
[I am not sure whether I need to post a new topic since this is a not related problem]

Error: @ Line42
System.NullReferenceException
Object reference not set to an instance of an object


My Code for btnUpdate (button)

Public Class Catalog
 
    Dim objConnection As SqlConnection = New SqlConnection _
        ("Data Source=WEIRDGUY-PC\SQLEXPRESS;Initial Catalog=StockInventory;Integrated Security=True")
 
    Dim objDataAdapter As New SqlDataAdapter()
    Dim objDataSet As New DataSet

Private Sub btnSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnUpdate.Click
 
        If String.IsNullOrEmpty(txtItemID.Text) Then
 
            MsgBox("Error: Part Number is Empty!")
            Exit Sub
        End If
 
        If String.IsNullOrEmpty(txtCat.Text) Then
 
            MsgBox("Error: Category is Empty!")
            Exit Sub
        End If
 
        Try
 
            'Declare local variables and objects...
            'Dim intPosition As Integer
            Dim objCommand As SqlCommand = New SqlCommand()
 
            'Save the current record position
            'intPosition = objCurrencyManager.Position
 
            objCommand.Connection = objConnection
            objCommand.CommandText = "UPDATE dbo.Item " & _
                                     "SET ItemDesc = @Desc, " & _
                                         "ItemCat = @Cat, " & _
                                         "ItemUnit = @Unit, " & _
                                         "ItemLoc = @Loc, " & _
                                         "ItemNotes = @Notes " & _
                                         "WHERE ItemID = @ItemID"
 
            'Parameters for Description
            objCommand.Parameters.AddWithValue("@Desc", txtDesc.Text)
            objCommand.Parameters.AddWithValue("@Cat", txtCat.Text)
            objCommand.Parameters.AddWithValue("@Unit", txtUnit.Text)
            objCommand.Parameters.AddWithValue("@Loc", txtLoc.Text)
            objCommand.Parameters.AddWithValue("@Notes", txtNotes.Text)
            objCommand.Parameters.AddWithValue("@ItemID", txtItemID.Text)
 
 
            objConnection.Open()    'Problem occurred at this line
 
            objCommand.ExecuteNonQuery()
 
            MessageBox.Show(txtItemID.Text & "had updated!")
 
            objConnection.Close()
 
        Catch ex As Exception
            MsgBox(ex.Message)
 
 
        End Try
 
    End Sub
End Class

[weirdguy]

Problem above solved. My mistake.

I moved @Line 6 Public Class

Dim objDataAdapter As New SqlDataAdapter()

to LoadDatagrdCatalog()