'-------------------------------------------------------------

'Lesson 3: L E A R N I N G   A S P . N E T


'                          Ron Kessler
'                         C# 206 Class
'-------------------------------------------------------------

'FEATURES:
'This beauty saves/gets one customer's information from "customers.txt" using streamreader/writer classes
'It shows how to get the default directory
'How to create a new test file in the application path
'How to close the browser using javascript
'Use the hyperlink control

'updated 3/24/08 for VS2005


Imports System.IO


Partial Class _Default
    Inherits System.Web.UI.Page

    '---define path to customer file
    Dim rootPath As String = Server.MapPath("~")
    Dim FileName As String = rootPath & "\asp-customers.txt"

#Region "Page Load"
    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

        '---this is a cool way to add a message box type function to a button on the web page.
        If Not IsPostBack Then
            Me.btnDone.Attributes.Add("onclick", "return confirm('Are you sure you want to quit?');")
        End If
    End Sub
#End Region

#Region "Create New File"

    Private Sub CreateFile()
        '---called from the btnSave_Click handler
        Dim MyWriter As StreamWriter = File.CreateText(FileName)
        MyWriter.Close()
    End Sub

#End Region

#Region "Save customer"
    Protected Sub btnSave_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnSave.Click

        '---save/get one customers data
        Try

            If Not File.Exists(FileName) Then
                CreateFile()
            End If

            Using MyWriter As New StreamWriter(FileName)

                MyWriter.WriteLine(txtLast.Text)
                MyWriter.WriteLine(txtFirst.Text)
                MyWriter.Close()

            End Using
        Catch
            lblError.Visible = True

        End Try
    End Sub

#End Region

#Region "Cancel"

    Protected Sub btnCancel_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnCancel.Click
        lblError.Visible = False
        txtFirst.Text = ""
        txtLast.Text = ""

    End Sub

#End Region

#Region "Get Customer"
    Protected Sub btnGet_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnGet.Click
        Try
            Using myReader As New StreamReader(FileName)

                txtLast.Text = myReader.ReadLine
                txtFirst.Text = myReader.ReadLine
                myReader.Close()
            End Using
        Catch
            lblError.Text = "I can't read the data file."
            lblError.Visible = True
        End Try
    End Sub
#End Region

#Region "Purchase"

    Protected Sub btnBuy_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnBuy.Click

        If Not File.Exists(rootPath & "\Streams.aspx") Then
            lblError.Text = "I can't find the Streams.aspx page."
            lblError.Visible = True
        Else
            '---navigate to the purchase page
            Response.Redirect("streams.aspx")
        End If

    End Sub

#End Region

#Region "Quit"

    Protected Sub btnDone_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnDone.Click

        '---close the browser
        Response.Write("<script language='javascript'> { window.close();}</script>")
    End Sub

#End Region
End Class