Most Useful Attributes in C#: From Beginner to Pro

Hello everyone! I started learning C# and came across something called attributes. So far I only understand that there is `[Obsolete]`, which marks a method as deprecated, and `[Serializable]` for serialization. But I feel like this is just the tip of the iceberg. For example, I'm writing a small logging application and noticed that I constantly duplicate access check code. Here's what I have now: ```csharp public void DeleteUser(int userId) { if (!HasAccess("Admin")) { Console.WriteLine("No access"); return; } // delete user Console.WriteLine("User deleted"); } ``` What if there are 20 methods? That's a nightmare. I've heard that attributes can somehow automate checks, logging, validation. But how? Which attributes are actually useful in everyday