Version: 2017.2

Description

This function is called when the object becomes enabled and active.

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour { void OnEnable() { print("script was enabled"); } }

Другой пример:

// Implement OnDisable and OnEnable script functions.
// These functions will be called when the attached GameObject
// is toggled.
// This example also supports the Editor.  The Update function
// will be called, for example, when the position of the
// GameObject is changed.

using UnityEngine;

[ExecuteInEditMode] public class PrintOnOff : MonoBehaviour { void OnDisable() { Debug.Log("PrintOnDisable: script was disabled"); }

void OnEnable() { Debug.Log("PrintOnEnable: script was enabled"); }

void Update() { #if UNITY_EDITOR Debug.Log("Editor causes this Update"); #endif } }

Note: OnEnable cannot be a co-routine.
See Also: OnDisable.