what do you put inside a if statement to get it to check if the object is touching something

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4.  
5. public class box : MonoBehaviour
6. { public SpriteRenderer sr;
7.      void Update()
8.     {
9.        if() this.sr.enabled = false;  
10.     }
11. }
12.  

so i want to make it so that if i touch something i go invisible by turning off and on the sprite renderer
but i dont know what to put inside the if statement to get input if im touching something or not

 

Have a look at how to use colliders.

 

i put a ontriggerenter and im getting a error saying it des not exist in the context

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4.  
5. public class box : MonoBehaviour
6. { public SpriteRenderer sr;
7.      void Update()
8.     {
9.         if (OnTriggerEnter) this.sr.enabled = false;
10.     }
11. }
12.  

 

do i need to make a variable?

 

FIXED IT THANKS