我终于找到问题了！

事实证明，我们使用 Unicode 编码编写文件，而不是 ASCII 或 UTF-8.更改 FileStream 上的编码似乎可以解决问题.

It turns out that we were writing the file using Unicode encoding, rather than ASCII or UTF-8. Changing the encoding on the FileStream seems to solve the problem.

感谢大家的建议！