1 第一种Physics2D.Raycast

RaycastHit2D hit = Physics2D.Raycast(Camera.main.ScreenToWorldPoint(Input.mousePosition), Vector2.zero); 

if(hit.collider != null)
{ 
Debug.Log ("Target Position: " + hit.collider.gameObject.transform.position);
}

2 第二种Physics2D.OverlapPointAll

Collider2D[] col = Physics2D.OverlapPointAll(Camera.main.ScreenToWorldPoint(Input.mousePosition));

 if(col.Length > 0)
 {
     foreach(Collider2D c in col)
     {
          //do what you want
     }
 }

当然可以

Collider2D col＝Physics2D.OverlapPoint(Camera.main.ScreenToWorldPoint(Input.mousePosition);