如何在c＃中拦截外部DLL的方法调用？

Question

我正在为Unity游戏解钩创建一个mod。有什么方法可以知道何时调用特定方法，以便我可以在完成时调用我的方法，而不是调用它？例如：

//This is the external method i want to intercept
public void OnPlayerJoin()
{
    Chat.WriteLine(NewPlayer.name + "has joined the game!");
}

---

//And here is my method that i want to call instead of it in process of interception
public void PlayerJoinHook()
{
    Chat.WriteLine(NewPlayer.name + "has joined the server! Don't forget to read rules!");
}