I’m working with a C# Telegram bot and I’m having trouble understanding how to properly get the latest message from users. The Telegram Bot API has a GetUpdates method that returns an array of messages along with update IDs and offsets. I know I need to use these update IDs to track which messages I’ve already processed, but I’m not sure about the correct approach to always fetch the most recent message that my bot received. Should I be looking at the highest update_id in the response? How do I make sure I don’t miss any messages or process the same message twice? Any help with the proper implementation would be great.
I ran into this exact issue when building my first Telegram bot. The key insight that helped me was understanding that GetUpdates is essentially a polling mechanism with built-in deduplication through the offset parameter. What worked reliably for me was implementing a simple loop where I call GetUpdates with a reasonable timeout (like 30 seconds), process all returned updates sequentially, then immediately call GetUpdates again with the offset set to the last processed update_id plus one. This approach ensures you never miss messages even if your bot goes offline temporarily, since unacknowledged updates remain in Telegram’s queue. One gotcha I discovered is that you should always process updates in the order they arrive rather than trying to jump to the “most recent” one, otherwise you might miss important context or commands that users sent earlier.
To ensure you are retrieving the most recent message using C# with the Telegram Bot API, maintain an offset that keeps track of the last processed update. When invoking GetUpdates, set the offset to the highest update_id from your last retrieval plus one. This way, you’ll only get new messages and prevent processing duplicates. I find it effective to save the last processed update_id in a text file or a database, and after handling the updates, update this stored value. The updates array provided by the API is sorted, allowing you to easily access the latest message by looking at the last element, but remember to check if the array is empty to avoid errors.
yeah the offset thing is key but dont forget to handle the case when getUpdates returns empty - your bot might crash otherwise. also store that last update_id somewhere persistent like a file, not just in memory or you’ll lose track after restart