Solve the same problem as the coordinates of the window obtained in the canvas

When using mouse events often want to get the current mouse x, y value, if the mouse event is a Window object, get the mouse x, Y is very simple, but when the mouse event is a window object, it is necessary to consider the position of the object in the window.

Because of the particularity of the canvas object, here I would like to analyze the problem of x, Y coordinates that need to be acquired when the mouse event is in the canvas object.

Here you need a method: Getboundingclientrect () to get the canvas of this rectangle object, if you want to know Getboundingclientrect () see http://jingyan.baidu.com/ Article/8cdccae960b041315413cdcd.html

Not much nonsense to say coding ....

<! DOCTYPE html>


Solve the same problem as the coordinates of the window obtained in the canvas