public void OpenWriteTest() { var path = @"z:\temp\aaa.txt"; var text = "あいうえお"; var file = new FileEmu(); using (Stream stream = file.OpenWrite(path)) { byte[] data = Encoding.GetEncoding("shift-jis").GetBytes(text); stream.Write(data, 0, data.Length); } Assert.AreEqual(text, file.ReadAllText(path, Encoding.GetEncoding("shift-jis"))); }