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Imports System。IO
Public Class Form1
    Private fn As String
    Private Sub Button1_Click(ByVal sender As System。
  Object, ByVal e As System。EventArgs) Handles Button1。Click
        Dim openFileDialog1 As New OpenFileDialog()
        Dim ErrMsg As String = ""
        openFileDialog1。
  InitialDirectory = Environment。GetFolderPath(Environment。SpecialFolder。MyDocuments)
        openFileDialog1。Filter = "文本文件 (*。
  TXT)|*。TXT|所有文件 (*。*)|*。*"
        openFileDialog1。FilterIndex = 1
        openFileDialog1。RestoreDirectory = True
        If openFileDialog1。
  ShowDialog() = Windows。Forms。DialogResult。OK Then
            fn = openFileDialog1。FileName
            Dim mysr As New StreamReader(fn, System。
  Text。Encoding。Default)
            RichTextBox1。Text = mysr。ReadToEnd
            mysr。Close()
        End If
    End Sub
    Private Sub Button2_Click(ByVal sender As System。
  Object, ByVal e As System。EventArgs) Handles Button2。Click
        Dim saveFileDialog1 As New SaveFileDialog
        Dim ErrMsg As String = ""
        saveFileDialog1。
  InitialDirectory = Environment。GetFolderPath(Environment。SpecialFolder。MyDocuments)
        saveFileDialog1。Filter = "文本文件 (*。
  TXT)|*。TXT|所有文件 (*。*)|*。*"
        saveFileDialog1。FilterIndex = 1
        saveFileDialog1。RestoreDirectory = True
        saveFileDialog1。
  FileName = fn
        If saveFileDialog1。ShowDialog() = Windows。Forms。DialogResult。OK Then
            fn = saveFileDialog1。
  FileName
            Dim mysw As New StreamWriter(fn, False, System。Text。Encoding。Default)
            mysw。Write(RichTextBox1。
  Text)
            mysw。Flush()
            mysw。Close()
        End If
    End Sub
End Class。