如何用vb.net编写读取txt内容的代码？

窗体上添加2个文本框，设置成多行，2个按钮，在文本框1里随便输入若干文字，可以多行，单击按钮1，保存到文件。然后单击按钮2，把刚才写入的文件读到文本框2里。
代码如下：
'写文本文件
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
'创建(写入)一个文本文件
Dim MyStream As New System.IO.FileStream(Application.StartupPath & "\Ssk.txt", System.IO.FileMode.Create)
Dim MyWriter As New System.IO.StreamWriter(MyStream, System.Text.Encoding.Default)
MyWriter.WriteLine(TextBox1.Text)
MyWriter.Flush()
MyWriter.Close()
MyStream.Close()
End Sub
'读文本文件
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
'读取一个文本文件
Dim MyReader As New System.IO.StreamReader(Application.StartupPath & "\Ssk.txt", System.Text.Encoding.UTF8)
TextBox2.Text = MyReader.ReadToEnd()
MyReader.Close()
End Sub
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