to record the length of the width of the webpage in js code example

Example 1: get window size javascript

const window {
  width: window.innerWidth,
  height: window.innerHeight
}

Example 2: how to get the size of the window in javascript

var win = window,
    doc = document,
    docElem = doc.documentElement,
    body = doc.getElementsByTagName('body')[0],
    x = win.innerWidth || docElem.clientWidth || body.clientWidth,
    y = win.innerHeight|| docElem.clientHeight|| body.clientHeight;
alert(x + ' × ' + y);