javascript获取隐藏dom的宽高 具体实现

  首先clone一个DOM,设置position:absolute,然后设置top为一个比较大的负值,然后使其显示出来,最后获取到了DOM的宽高后,将其remove。

  具体代码如下:

  Js代码

  

复制代码 代码如下:

  function getCss(elem, css){

  if (window.getComputedStyle) {

  return window.getComputedStyle(elem, null)[css];

  }else if (elem.currentStyle) {

  return elem.currentStyle[css];

  }else {

  return elem.style[css];

  }

  }

  function getWH(dom){

  var get = function(elem){

  var wh = {};

  'Width Height'.replace(/[^ ]+/g, function(i){

  var a = i.toLowerCase();

  wh[a] = elem['offset' + i] || elem['client' + i];

  });

  return wh;

  };

  if (getCss(dom, 'display') === 'none') {

  var nDom = dom.cloneNode(true);

  nDom.style.position = 'absolute';

  nDom.style.top = '-3000px';

  nDom.style.display = 'block';

  document.getElementsByTagName('body')[0].appendChild(nDom);

  var wh = get(nDom);

  nDom.parentNode.removeChild(nDom);

  return wh;

  }

  return get(dom);

  }

  //test

  console.log(getWH(document.getElementById('content')));

  var domA = document.createElement("a"), _ostyle = "position:absolute;z-index:999999;width:92px;height:22px;position:absolute;display:none;";

  domA.setAttribute("style", _ostyle);

  domA.style.cssText = _ostyle;

  domA.setAttribute("href", "javascript:void(0);");

  document.getElementsByTagName('body')[0].appendChild(o);

  console.log(getWH(domA));

  function getCss(elem, css){

  if (window.getComputedStyle) {

  return window.getComputedStyle(elem, null)[css];

  }else if (elem.currentStyle) {

  return elem.currentStyle[css];

  }else {

  return elem.style[css];

  }

  }

  function getWH(dom){

  var get = function(elem){

  var wh = {};

  'Width Height'.replace(/[^ ]+/g, function(i){

  var a = i.toLowerCase();

  wh[a] = elem['offset' + i] || elem['client' + i];

  });

  return wh;

  };

  if (getCss(dom, 'display') === 'none') {

  var nDom = dom.cloneNode(true);

  nDom.style.position = 'absolute';

  nDom.style.top = '-3000px';

  nDom.style.display = 'block';

  document.getElementsByTagName('body')[0].appendChild(nDom);

  var wh = get(nDom);

  nDom.parentNode.removeChild(nDom);

  return wh;

  }

  return get(dom);

  }

  //test

  console.log(getWH(document.getElementById('content')));

  var domA = document.createElement("a"), _ostyle = "position:absolute;z-index:999999;width:92px;height:22px;position:absolute;display:none;";

  domA.setAttribute("style", _ostyle);

  domA.style.cssText = _ostyle;

  domA.setAttribute("href", "javascript:void(0);");

  document.getElementsByTagName('body')[0].appendChild(o);

  console.log(getWH(domA));

  还有其他更好的方法欢迎提出来。