frmbrokenchild.vb

清华大学出版社出版的 移动应用开发宝典 张大威（2008）的附书源代码

Imports Microsoft.VisualBasic
Imports System
Imports System.Windows.Forms
Imports System.Drawing

Namespace CodeForChapter2
  Partial Public Class frmBrokenChild
    Inherits CodeForChapter2.frmBaseWithSIP
    Public Sub New()
      InitializeComponent()
    End Sub


    Private lastIndex As Integer = 0
    Private Sub tabControl1_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs) Handles tabControl1.SelectedIndexChanged
      Dim newIndex As Integer = tabControl1.SelectedIndex
      If newIndex = lastIndex Then
        ' validation failed
        tabControl1.TabPages(lastIndex).BackColor = Color.Red

        ' prevent infinite loop
        Return
      End If

      If checkBox1.Checked Then ' your own validation logic
        tabControl1.SelectedIndex = lastIndex ' raises this event again
        Return
      End If

      ' update our knowledge
      tabControl1.TabPages(lastIndex).BackColor = Color.White
      lastIndex = newIndex
    End Sub
  End Class
End Namespace