如何使用javascript document.getSelecttion（）在html中获取所选文本的坐标
问题描述：
我想将元素放在选定文本上方。但我无法弄清楚坐标。
I would like to position element above selected text. But I am not able to figure out the coordinates.
var sel = document.getSelection();
if(sel != null) {
positionDiv();
}
示例:(图片）
答
这是基本想法。您在选择的开头插入虚拟元素，并获取该虚拟html元素的坐标。然后你删除它。
Here is the basic idea. You insert dummy element in the beginning of the selection and get the coordinates of that dummy html element. Then you remove it.
var range = window.getSelection().getRangeAt(0);
var dummy = document.createElement("span");
range.insertNode(dummy);
var box = document.getBoxObjectFor(dummy);
var x = box.x, y = box.y;
dummy.parentNode.removeChild(dummy);