How to intercept/modify keystrokes before the Microsoft Chinese IME processes them on Windows?

I’m using Microsoft IME (Chinese Simplified) and I need to type a backslash ( \ ) while Chinese mode is active. However, when I press the backslash key, the IME always converts it into the Chinese punctuation 、 (ideographic comma). On my physical keyboard, the same key has both 、 and \ printed on it, and normally a modifier like Shift/Alt/Ctrl should give me access to the backslash. But with Microsoft IME enabled, no modifier produces a real backslash — the IME rewrites it every time. Switching the input method into English mode does allow typing a backslash, but constantly switching back and

Question by Vade Cas on Super User, licensed CC BY-SA. We show a short excerpt and link to the original thread as credit.