求助，高手请赐教

汗，這個也要叫高手，現在的人，越來越不想自己動手了.哎！
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim x As Integer = Me.ListBox1.Items.Count
        Dim strTemp, strTemp01, strTemp02, strTemp03, strtemp04 As String
        Dim flag As Boolean = False
        strTemp01 = Me.TextBox1.Text
        strTemp02 = Me.TextBox2.Text
        strTemp03 = Me.TextBox3.Text
        strtemp04 = Me.TextBox4.Text
        If x = 0 Then
            Me.ListBox1.Items.Add(strTemp01)
            Me.ListBox1.Items.Add(strTemp02)
            Me.ListBox1.Items.Add(strTemp03)
            Me.ListBox1.Items.Add(strtemp04)
        Else

            For i As Integer = 0 To x - 1
                strTemp = Me.ListBox1.Items(i).ToString
                If strTemp01 = strTemp Or strTemp02 = strTemp Or strTemp03 = strTemp Or strtemp04 = strTemp Then
                    flag = True
                End If
            Next
            If flag = False Then
                Me.ListBox1.Items.Add(strTemp01)
                Me.ListBox1.Items.Add(strTemp02)
                Me.ListBox1.Items.Add(strTemp03)
                Me.ListBox1.Items.Add(strtemp04)
            End If

        End If


    End Sub