![error CS1061: Type `UnityEngine.Component' does not contain a definition for `AddForce' and no extension method `AddForce' of type `UnityEngine.Component' could be found. Are you missing an assembly reference? - Unity Answers error CS1061: Type `UnityEngine.Component' does not contain a definition for `AddForce' and no extension method `AddForce' of type `UnityEngine.Component' could be found. Are you missing an assembly reference? - Unity Answers](https://answers.unity.com/storage/temp/86346-capture1.png)
error CS1061: Type `UnityEngine.Component' does not contain a definition for `AddForce' and no extension method `AddForce' of type `UnityEngine.Component' could be found. Are you missing an assembly reference? - Unity Answers
![error CS1061: Type `BasePlayer' does not contain a definition for `PlayerClass' and no extension method `PlayerClass' of type `BasePlayer' could be found (are you missing a using directive or an assembly reference?) - error CS1061: Type `BasePlayer' does not contain a definition for `PlayerClass' and no extension method `PlayerClass' of type `BasePlayer' could be found (are you missing a using directive or an assembly reference?) -](https://answers.unity.com/storage/temp/69181-zrzut-ekranu-2016-05-01-o-172610.png)
error CS1061: Type `BasePlayer' does not contain a definition for `PlayerClass' and no extension method `PlayerClass' of type `BasePlayer' could be found (are you missing a using directive or an assembly reference?) -
![Binary Impact on Twitter: "#UnityTips You can actually inject functions into classes with extension methods 🤩 This is great for extending functionality of any class, such as Vector3, GameObject, MonoBehaviour, etc. 🤯 Binary Impact on Twitter: "#UnityTips You can actually inject functions into classes with extension methods 🤩 This is great for extending functionality of any class, such as Vector3, GameObject, MonoBehaviour, etc. 🤯](https://pbs.twimg.com/media/FHHqhlJXoAI5Jaa.png)
Binary Impact on Twitter: "#UnityTips You can actually inject functions into classes with extension methods 🤩 This is great for extending functionality of any class, such as Vector3, GameObject, MonoBehaviour, etc. 🤯
![Freya Holmér on Twitter: "I just found a super nice C# trick for allocation free structs with shared functionality • structs can't inherit from structs • Unity doesn't support default interface implementations Freya Holmér on Twitter: "I just found a super nice C# trick for allocation free structs with shared functionality • structs can't inherit from structs • Unity doesn't support default interface implementations](https://pbs.twimg.com/media/E6LPrGWWQAIeLaq.png:large)