why does TextBox1 show nothing?

I want to click a button and TextBox1 show the content of the file "1.txt"

but failed why??

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles Button2.Click
FileOpen(1, "c:\1.txt", OpenMode.Binary)
FileGet(1, TextBox1.Text)
FileClose()
'TextBox1.Update()
'TextBox1.Refresh()
Dim mylen As Integer
mylen = TextBox1.TextLength() ' mylen is 0,,,,really strange I
think mylen = len of "1.txt"
End Sub



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