Stopping coroutines in Unity - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a coroutine in Unity?

A coroutine is a special function that can pause execution and resume later, allowing you to run code over multiple frames without blocking the main game loop.

beginner

How do you start a coroutine in Unity?

You start a coroutine by calling StartCoroutine(MethodName()) inside a MonoBehaviour script.

intermediate

What method is used to stop a running coroutine by its name?

You can stop a coroutine by calling StopCoroutine("MethodName"), passing the coroutine's method name as a string.

intermediate

How can you stop a coroutine using a Coroutine variable?

When you start a coroutine, you can save its reference like Coroutine myCoroutine = StartCoroutine(MethodName()). Then stop it by calling StopCoroutine(myCoroutine).

intermediate

What happens if you call StopAllCoroutines() in a MonoBehaviour?

It stops all coroutines running on that MonoBehaviour immediately, cancelling all paused or running coroutine executions.

Which method stops all coroutines running on a MonoBehaviour?

A StopAllCoroutines()

B StopCoroutine()

C EndCoroutine()

D CancelCoroutine()

StopAllCoroutines() stops every coroutine running on the MonoBehaviour. The others are incorrect or do not exist.

How do you stop a coroutine if you only know its method name?

A StopCoroutine(coroutineVariable)

B StopCoroutine(MethodName())

C StopCoroutine("MethodName")

D StopAllCoroutines()

Use the method name as a string in StopCoroutine to stop it by name.

What must you save when starting a coroutine to stop it later by reference?

A Coroutine variable from StartCoroutine()

B Method name string

C IEnumerator variable

D GameObject reference

Saving the Coroutine returned by StartCoroutine() lets you stop it later by passing that variable.

What happens if you call StopCoroutine on a coroutine that is not running?

A Throws an exception

B Nothing happens, no error

C Restarts the coroutine

D Pauses the coroutine

Calling StopCoroutine on a non-running coroutine does nothing and does not cause errors.

Which of these is NOT a valid way to stop a coroutine?

A StopCoroutine(coroutineVariable)

B StopCoroutine("MethodName")

C StopCoroutine(IEnumerator variable)

D StopCoroutine(GameObject)

You cannot stop a coroutine by passing a GameObject. The others are valid ways.

Explain how to stop a coroutine in Unity using both the method name and Coroutine variable approaches.

Think about the two common ways Unity lets you stop coroutines.

Describe what StopAllCoroutines does and when you might want to use it.

Consider a situation where many coroutines run and you want to stop them all quickly.