lab2

Option Explicit On
Option Strict On
Option Infer Off
Public Class Form1
    Structure person
        Public name As String
        Public height As Double
        Public weight As Double
    End Structure
    Dim database(49) As person
    Dim counter As Integer = 0
    Private Sub btnSubmit_Click(sender As Object, e As EventArgs) Handles btnSubmit.Click
        Dim height As Double = 0
        Dim weight As Double = 0
        If counter > 49 Then
            MsgBox("The database is full.", MsgBoxStyle.Critical)
        ElseIf (txtName.Text.Trim = "") Then
            MsgBox("Please enter a name.", MsgBoxStyle.Critical)
        ElseIf Not Double.TryParse(txtHeight.Text, height) Then
            MsgBox("Please enter a height.", MsgBoxStyle.Critical)
        ElseIf Not Double.TryParse(txtWeight.Text, weight) Then
            MsgBox("Please enter a weight.", MsgBoxStyle.Critical)
        Else
            database(counter).name = txtName.Text.Trim
            database(counter).weight = weight
            database(counter).height = height
            lstName.Items.Add(txtName.Text.Trim)
            lstWeight.Items.Add(weight)
            lstHeight.Items.Add(height)
            txtHeight.Text = ""
            txtName.Text = ""
            txtWeight.Text = ""
            counter += 1
        End If

    End Sub

    Private Sub btnSave_Click(sender As Object, e As EventArgs) Handles btnSave.Click
        If Not counter = 0 Then
            Dim outfile As IO.StreamWriter
            If IO.File.Exists("class.txt") Then
                If MsgBox("Do you wish to overwrite the current saved file?", MsgBoxStyle.YesNo) = MsgBoxResult.Yes Then
                    IO.File.Delete("class.txt")
                    outfile = IO.File.CreateText("class.txt")
                    For i As Integer = 0 To (counter - 1) Step 1
                        outfile.WriteLine(database(i).name)
                        outfile.WriteLine(database(i).height.ToString)
                        outfile.WriteLine(database(i).weight.ToString)
                    Next
                    outfile.Close()
                    MsgBox("Save successfull.", MsgBoxStyle.Information)
                Else
                    MsgBox("Save Aborted.", MsgBoxStyle.Information)
                End If
            Else
                outfile = IO.File.CreateText("class.txt")
                For i As Integer = 0 To (counter - 1) Step 1
                    outfile.WriteLine(database(i).name)
                    outfile.WriteLine(database(i).height.ToString)
                    outfile.WriteLine(database(i).weight.ToString)
                Next
                outfile.Close()
                MsgBox("Save successfull.", MsgBoxStyle.Information)
            End If
        Else
            MsgBox("You have no records to save.", MsgBoxStyle.Critical)
        End If

    End Sub

    Private Sub btnRead_Click(sender As Object, e As EventArgs) Handles btnRead.Click
        Dim infile As IO.StreamReader
        If IO.File.Exists("class.txt") Then
            infile = IO.File.OpenText("class.txt")
            lstName.Items.Clear()
            lstHeight.Items.Clear()
            lstWeight.Items.Clear()
            counter = 0
            Dim temp As Double = 0
            While Not infile.Peek = -1
                database(counter).name = infile.ReadLine()
                lstName.Items.Add(database(counter).name)
                Double.TryParse(infile.ReadLine(), temp)
                database(counter).height = temp
                lstHeight.Items.Add(temp)
                Double.TryParse(infile.ReadLine(), temp)
                database(counter).weight = temp
                lstWeight.Items.Add(temp)
                counter += 1
            End While
            infile.Close()
            MsgBox("Load successfull.", MsgBoxStyle.Information)
        Else
            MsgBox("File not found!", MsgBoxStyle.Critical)
        End If
    End Sub

    Private Sub btnClear_Click(sender As Object, e As EventArgs) Handles btnClear.Click
        If IO.File.Exists("class.txt") Then
            IO.File.Delete("class.txt")
            MsgBox("File Deleted.", MsgBoxStyle.Information)
        Else
            MsgBox("File not found!", MsgBoxStyle.Critical)
        End If
    End Sub

    Private Sub txtHeight_KeyPress(sender As Object, e As KeyPressEventArgs) Handles txtHeight.KeyPress, txtWeight.KeyPress
        If (e.KeyChar < "0" OrElse e.KeyChar > "9") AndAlso e.KeyChar <> ControlChars.Back Then
            e.Handled = True
        End If
    End Sub

    Private Sub QuitToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles QuitToolStripMenuItem.Click
        Me.Close()
    End Sub

    Private Sub Form1_FormClosing(sender As Object, e As FormClosingEventArgs) Handles Me.FormClosing
        If Not counter = 0 Then
            If MsgBox("Do you wish to save?", MsgBoxStyle.YesNo) = MsgBoxResult.Yes Then
                Dim outfile As IO.StreamWriter
                If IO.File.Exists("class.txt") Then
                    If MsgBox("Do you wish to overwrite the current saved file?", MsgBoxStyle.YesNo) = MsgBoxResult.Yes Then
                        IO.File.Delete("class.txt")
                        outfile = IO.File.CreateText("class.txt")
                        For i As Integer = 0 To (counter - 1) Step 1
                            outfile.WriteLine(database(i).name)
                            outfile.WriteLine(database(i).height.ToString)
                            outfile.WriteLine(database(i).weight.ToString)
                        Next
                        outfile.Close()
                        MsgBox("Save successfull.", MsgBoxStyle.Information)
                    Else
                        MsgBox("Save Aborted.", MsgBoxStyle.Information)
                    End If
                Else
                    outfile = IO.File.CreateText("class.txt")
                    For i As Integer = 0 To (counter - 1) Step 1
                        outfile.WriteLine(database(i).name)
                        outfile.WriteLine(database(i).height.ToString)
                        outfile.WriteLine(database(i).weight.ToString)
                    Next
                    outfile.Close()
                    MsgBox("Save successfull.", MsgBoxStyle.Information)
                End If
            End If
        End If
    End Sub

    Private Sub txtWeight_TextChanged(sender As Object, e As EventArgs) Handles txtWeight.TextChanged

    End Sub
End Class