.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.EventSystems;

public class buttontest : MonoBehaviour {

    // Use this for initialization
    void Start()
    {
        EventTrigger trigger = GetComponent<EventTrigger>();

        EventTrigger.Entry PointerClick = new EventTrigger.Entry();

        PointerClick.eventID = EventTriggerType.PointerDown;
        PointerClick.callback.AddListener((data) => { count = 0; clicking = true; });
        trigger.triggers.Add(PointerClick);

        EventTrigger.Entry PointerUp = new EventTrigger.Entry();

        PointerUp.eventID = EventTriggerType.PointerUp;
        PointerUp.callback.AddListener((data) => {
            print(count);
            if (count > 3 && count <= 6)
            {
                print("EjecutarAccion1");
            }
            else if (count > 6)
            {
                print("Ejecutaraccion2");
            }
            clicking = false;
            count = 0;
        });
        trigger.triggers.Add(PointerUp);

    }

    bool clicking;
    float count;

    private void Update()
    {
        if (clicking)
        {
            count += Time.deltaTime;
        }
    }

}