Activate an input to pickup or search objectes

Hey,

I'm currently working on a script to pickup things or search a box, which may could contain some items. I set up the script with a trigger methode. Now, my problem is, that if I hit the assigned key, I get no response. After reading the documentation, I know, that "Input" should or must be called in the update methode.

Now I don't know how to combine these to methodes. I hope you could help me.

Here is the code I have written so far:

 using UnityEngine;
 using System.Collections;
 using UnityEngine.UI;
 
 public class ContentResponse : MonoBehaviour {
 
     public Text display;
     public bool key = false;
 
     void OnTriggerEnter(Collider other)
     {
         if (other.tag == "Player")
         {
             display.text = "Drücke E um die Kiste zu durchsuchen.";

//"press E to search the box"

         }
         if (Input.GetKeyDown(KeyCode.E))
         {
             Debug.Log("Gefunden"); //"found"
             key = true;
         }
         Input.ResetInputAxes();
     }
     void OnTriggerExit(Collider other)
     {
         display.text = "";
     }
 
     // Use this for initialization
     void Start () 
     {
         display.text = "";
 
     }  
     
     // Update is called once per frame
     void Update () 
     {
 
 
     }
 ...