Unity 5 2D Camera Bounds

I need help making camera boundaries for my 2D game. I want the camera to stop when it hits the edge of the level, but start following the player again if he moves the other way into the level again. I’m pretty new to C# so I don’t really know how I’m going to do this. Any ideas?

Here is the scripts that tells the camera to follow the player:

using UnityEngine;
using System.Collections;

public class FollowPlayer : MonoBehaviour {
	
	public PlayerController player;
	
	public bool isFollowing;
	
	public float xOffset;
	public float yOffset;

	// Use this for initialization
	void Start () {
		player = FindObjectOfType<PlayerController> ();
		
		isFollowing = true;
	}

	// Update is called once per frame
	void Update () {
		if(isFollowing) {
			transform.position = new Vector3(player.transform.position.x + xOffset, player.transform.position.y + yOffset, transform.position.z);
		}
	}
}

I’ve also tried to set isFollowing to false every time the player hits a certain trigger, but whenever the player went back into the level, the camera just jumped to the player, which didn’t look very good.

@Gooball60

pako has suggested one of the simplest way but still if you dont want to make the camera child of player you can clamp the position of the camera to restrict its movement in space