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  • 03JavaScript程序设计修炼之道 2019-06-27_20-34-17 文本节点创建、文档碎片

    16textNode.html

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <meta name="viewport" content="width=device-width, initial-scale=1.0">
        <meta http-equiv="X-UA-Compatible" content="ie=edge">
        <title>Document</title>
    </head>
    <body>
        <script>
            window.onload = function() {
                /*
                var oDiv = document.createElement("div");
                var oTxt = document.createTextNode("hi");
                oDiv.appendChild(oTxt);
                document.body.appendChild(oDiv);
                */
                // 在页面中打印999个按钮
                var t1 = new Date().getTime();
                /*
                for(var i=0; i<999; i++) {
                    document.body.innerHTML += "<input type='button' value='按钮'/>";
                } // 2193
                */
               /*
                var str = "";
                for(var i=0; i<999; i++) {
                    str += "<input type='button' value='按钮'/>";
                }
                document.body.innerHTML = str; // 4
                */
                // 文档碎片   === 缓存
                var cache = document.createDocumentFragment();
                for(var i=0; i<9999; i++) {
                    var opt = document.createElement("input");
                    opt.type = "button";
                    opt.value = "按钮";
                    cache.appendChild(opt);
                }
                document.body.appendChild(cache);
                var t2 = new Date().getTime();
                console.log(t2-t1);  
            }
        </script>
    </body>
    </html>

     

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  • 原文地址:https://www.cnblogs.com/HiJackykun/p/11108331.html
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