how to create onclick button in unity code example

Example 1: how to code button click unity

using UnityEngine;
using UnityEngine.UI;
using System.Collections;
public class ClickExample : MonoBehaviour {
	public Button yourButton;	
    
    void Start () {
		Button btn = yourButton.GetComponent<Button>();
		btn.onClick.AddListener(TaskOnClick);
	}	
    void TaskOnClick(){
		Debug.Log ("You have clicked the button!");
	}
}

Example 2: unity onclick object

void Update () {
     
 }
  void OnMouseDown(){
         // this object was clicked - do something
     Destroy (this.gameObject);
  }