ie11 Element.children 填充

Question

I'm working on a project in which I use es6 code with babel. I use the following code:

 let result= xmlDocument.querySelector("xmlNodeSelector");

 for (let child of  result.children) { /* do something */ }

The problem it doens't work on IE11 since no children property.

I create the following polyfill but it didn't help:

if(Element.prototype.hasOwnProperty('children')){
            return;
        }

        Object.defineProperty(Element.prototype, 'children', {
            get: function(){

                let children = new HTMLCollection();

                for(let i=0; i < this.childNodes.length; i++){
                    let item = this.childNodes[i];

                    if(item.nodeName !== '#text'){
                        children.push(item);
                    }
                }

                return children;
            }
        });

When I debug IE11 I can see the prototype is Element but the property is not added. In addition when using:

selectorResult instanceof Element
selectorResult instanceof Node

I get false on both.

At the moment I use a method to extract children rather then adding to the prototype which is what i prefer.

Any suggestions?

Thanks in advance

Answer 1

The following code adds the property children to all HTML,XML and SVG elements - just tested it under IE11:

//make sure we have Node.children and Element.children available
(function (constructor) {
    if (constructor &&
        constructor.prototype &&
        constructor.prototype.children == null) {
        Object.defineProperty(constructor.prototype, 'children', {
            get: function () {
                var i = 0, node, nodes = this.childNodes, children = [];
                //iterate all childNodes
                while (node = nodes[i++]) {
                    //remenber those, that are Node.ELEMENT_NODE (1)
                    if (node.nodeType === 1) { children.push(node); }
                }
                return children;
            }
        });
    }
  //apply the fix to all HTMLElements (window.Element) and to SVG/XML (window.Node)
})(window.Node || window.Element);

I found that polyfill on MDN.

This polyfill will return an array , instead of an HTMLCollection , but you can still make use of Node.children.length and Node.children[index] .

Using this polyfill you could iterate your result like this:

var resChildren = result.children
var index, maxindex;
for (index=0, maxindex=resChildren.length; index<maxindex; index++) 
{
    /* do_something_with(resChildren[index]); */
}