[Visual Basic]
Public Sub LoadMyFile()
' Create an OpenFileDialog to request a file to open.
Dim openFile1 As New OpenFileDialog()
' Initialize the OpenFileDialog to look for RTF files.
openFile1.DefaultExt = "*.rtf"
openFile1.Filter = "RTF Files|*.rtf"
' Determine whether the user selected a file from the OpenFileDialog.
If (openFile1.ShowDialog() = System.Windows.Forms.DialogResult.OK) _
And (openFile1.FileName.Length > 0) Then
' Load the contents of the file into the RichTextBox.
richTextBox1.LoadFile(openFile1.FileName, _
RichTextBoxStreamType.PlainText)
End If
End Sub