Chapter 8

demac3 · November 3rd, 2010, 11:43 AM

I have an error in my MasterPage that I can't figure out. I'm sure I've done something wrong because this book is fantastic!

The error: Error 1 c:\BegASPNET\Site\MasterPages\Frontend.master.vb(2 7): error BC30311: Value of type 'Boolean' cannot be converted to 'System.Web.UI.WebControls.TreeView'.

Code:

Partial Class MasterPages_Frontend
  Inherits System.Web.UI.MasterPage

  Protected Sub ThemeList_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles ThemeList.SelectedIndexChanged
    Dim preferredTheme As HttpCookie = New HttpCookie("PreferredTheme")
    preferredTheme.Expires = DateTime.Now.AddMonths(3)
    preferredTheme.Value = ThemeList.SelectedValue
    Response.Cookies.Add(preferredTheme)
    Response.Redirect(Request.Url.ToString())
  End Sub

  Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
    If Not Page.IsPostBack Then
      Dim selectedTheme As String = Page.Theme
      Dim preferredTheme As HttpCookie = Request.Cookies.Get("PreferredTheme")
      If preferredTheme IsNot Nothing Then
        selectedTheme = preferredTheme.Value
      End If
      If Not String.IsNullOrEmpty(selectedTheme) AndAlso ThemeList.Items.FindByValue(selectedTheme) IsNot Nothing Then
        ThemeList.Items.FindByValue(selectedTheme).Selected = True
      End If
        End If
        Select Case Page.Theme.ToLower()
            Case "darkgrey"
                Menu1.Visible = False
                TreeView1 = True
            Case Else
                Menu1.Visible = True
                TreeView1 = False
        End Select
        
  End Sub

End Class

Imar · November 3rd, 2010, 12:00 PM

Quote:

I'm sure I've done something wrong because this book is fantastic!

That's good to hear!

Take a look at this code:

Code:

 
Case "darkgrey"
  Menu1.Visible = False
  TreeView1 = True
Case Else
  Menu1.Visible = True
  TreeView1 = False

You're trying to assign True or False to the entire TreeView. Instead you need to assign it to its Visible property:

Code:

 
Case "darkgrey"
  Menu1.Visible = False
  TreeView1.Visible = True
Case Else
  Menu1.Visible = True
  TreeView1.Visible = False

Hope this helps,

Imar

demac3 · November 3rd, 2010, 01:55 PM

Tahnks a million!

As it turned out, I had copied your source file. However, it created a new directory and, in fact, never overlayed my file with the error. All along I thought I was looking at your source code! Live and learn!

Thanks, again.

Ps. I'm sending you a new problem. Seems I do little except read your book and do the exercises. It is a lot of fun!