[vbnet]

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تذكرت أمر أسهل لا تحتاج لمرجع Reference

كود :

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
    Using op As New OpenFileDialog
        op.Filter = "Excel files (*.xls,xlsx)|*.xls;*.xlsx"
        If op.ShowDialog = DialogResult.OK Then

            Process.Start(op.FileName)

        End If
    End Using
End Sub

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