vb.net 打字练习

Public Class Form1
    Dim t As Date
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim inputdata As String
        OpenFileDialog1.FileName = "*txt"
        OpenFileDialog1.InitialDirectory = "C:/Documents and Settings/Administrator/桌面/指法练习/指法练习/bin/Debug"
        OpenFileDialog1.Filter = "text files(*.txt)|*.txt|all iles(*.*)|*.*"
        OpenFileDialog1.FilterIndex = 2
        OpenFileDialog1.ShowDialog()
        FileOpen(1, OpenFileDialog1.FileName, OpenMode.Input)
        RichTextBox1.Text = ""
        Do While Not EOF(1)
            inputdata = LineInput(1)
            RichTextBox1.Text = RichTextBox1.Text + inputdata + vbCrLf
        Loop
        FileClose(1)
    End Sub

    Private Sub RichTextBox2_GotFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles RichTextBox2.GotFocus
        t = TimeOfDay
    End Sub

    Private Sub RichTextBox2_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles RichTextBox2.KeyDown
        Dim l As Integer
        l = RichTextBox2.TextLength
        Dim t2, n, y, i As Integer
        If e.KeyCode = Keys.Enter Then
            t2 = DateDiff("s", t, TimeOfDay)
            TextBox1.Text = t2 & "秒"
            RichTextBox2.ReadOnly = True
            y = 0 : n = 0
            For i = 1 To l
                If Mid(RichTextBox1.Text, i, 1) = Mid(RichTextBox2.Text, i, 1) Then
                    y = y + 1
                Else
                    n = n + 1
                End If
            Next i
            y = y / l * 100
            TextBox2.Text = Format(y, "0.00") & "%"

        End If
    End Sub
    Private Sub RichTextBox2_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles RichTextBox2.KeyPress
        Dim t2, n, y, i As Integer
        If RichTextBox2.TextLength + 1 = RichTextBox1.TextLength Then
            t2 = DateDiff("s", t, TimeOfDay)
            TextBox1.Text = t2 & "秒"
            RichTextBox2.ReadOnly = True
            y = 0 : n = 0
            For i = 1 To 4
                If Mid(RichTextBox1.Text, i, 1) = Mid(RichTextBox2.Text, i, 1) Then
                    y = y + 1
                Else
                    n = n + 1
                End If
            Next i
            y = y / 4 * 100
            TextBox2.Text = Format(y, "0.00") & "%"
        End If
    End Sub