如何获得Click的位置？

I'm currently making a game where the player will click on one of his units (which are pictureboxes) and a circle will become visible with the player's unit in the center. (Circle is also a picturebox) When the player clicks on the picturebox of the circle I need to figure out if the position of the click is inside the radius of the circle. My question is how do I get the position of the click?I'm currently making a game where the player wi