How to find the element's x center coordinates and related window offset

问题

i would like to retrieve the element offset starting from his own x center coordinates.

how can i do it?

Actually i can find the window offset of an element but it retrieves the coordinates from the border of the element like this:

var _position = $(this).offset();

回答1:

You have to use offset() to get the top and left position, then add half of the height() and width() values to them. That gives the center coordinates.

var $this = $(this);
var offset = $this.offset();
var width = $this.width();
var height = $this.height();

var centerX = offset.left + width / 2;
var centerY = offset.top + height / 2;

If you need to consider the padding property in your calculations, use the following:

var width = $this.outerWidth();
var height = $this.outerHeight();

回答2:

This can now be done through native Javascript also:

let centerX = targetNode.offsetLeft + targetNode.offsetWidth / 2;
let centerY = targetNode.offsetTop + targetNode.offsetHeight / 2;

where targetNode is the element you want to get its center coordinates.

来源：https://stackoverflow.com/questions/8027875/how-to-find-the-elements-x-center-coordinates-and-related-window-offset