<p><button class="runcode" title="runcode2" type="button">运行代码</button></p> <p>原书中说：IE中nextSibling比childNodes表现优异。在IE6中，nextSibling快16倍，IE7中是105倍。</p> <p>经测试后发现：IE7下：nextSibling要快一些，childNodes与childnren速度相当。IE6下：nextSibling与childNodes差别相当大，children稍快。FF下还是nextSibling快一点。</p> <div class="likecs_code"> <div> <span style="color: rgba(0, 0, 255, 1)">function</span><span style="color: rgba(0, 0, 0, 1)"> testNextSibling(){<br> </span><span style="color: rgba(0, 0, 255, 1)">var</span><span style="color: rgba(0, 0, 0, 1)"> el </span><span style="color: rgba(0, 0, 0, 1)">=</span><span style="color: rgba(0, 0, 0, 1)"> $(</span><span style="color: rgba(0, 0, 0, 1)">'</span><span style="color: rgba(0, 0, 0, 1)">mydiv</span><span style="color: rgba(0, 0, 0, 1)">'</span><span style="color: rgba(0, 0, 0, 1)">),<br> ch </span><span style="color: rgba(0, 0, 0, 1)">=</span><span style="color: rgba(0, 0, 0, 1)"> el.firstChild,<br> name </span><span style="color: rgba(0, 0, 0, 1)">=</span><span style="color: rgba(0, 0, 0, 1)"> </span><span style="color: rgba(0, 0, 0, 1)">''</span><span style="color: rgba(0, 0, 0, 1)">;<br> </span><span style="color: rgba(0, 0, 255, 1)">do</span><span style="color: rgba(0, 0, 0, 1)"> {<br> name </span><span style="color: rgba(0, 0, 0, 1)">=</span><span style="color: rgba(0, 0, 0, 1)"> ch.nodeName;<br> } </span><span style="color: rgba(0, 0, 255, 1)">while</span><span style="color: rgba(0, 0, 0, 1)"> (ch </span><span style="color: rgba(0, 0, 0, 1)">=</span><span style="color: rgba(0, 0, 0, 1)"> ch.nextSibling);<br> </span><span style="color: rgba(0, 0, 255, 1)">return</span><span style="color: rgba(0, 0, 0, 1)"> name;<br> }<br></span><span style="color: rgba(0, 0, 255, 1)">function</span><span style="color: rgba(0, 0, 0, 1)"> testChildNodes(){<br> </span><span style="color: rgba(0, 0, 255, 1)">var</span><span style="color: rgba(0, 0, 0, 1)"> el </span><span style="color: rgba(0, 0, 0, 1)">=</span><span style="color: rgba(0, 0, 0, 1)"> $(</span><span style="color: rgba(0, 0, 0, 1)">'</span><span style="color: rgba(0, 0, 0, 1)">mydiv</span><span style="color: rgba(0, 0, 0, 1)">'</span><span style="color: rgba(0, 0, 0, 1)">),<br> ch </span><span style="color: rgba(0, 0, 0, 1)">=</span><span style="color: rgba(0, 0, 0, 1)"> el.childNodes,<br> len </span><span style="color: rgba(0, 0, 0, 1)">=</span><span style="color: rgba(0, 0, 0, 1)"> ch.length,<br> name </span><span style="color: rgba(0, 0, 0, 1)">=</span><span style="color: rgba(0, 0, 0, 1)"> </span><span style="color: rgba(0, 0, 0, 1)">''</span><span style="color: rgba(0, 0, 0, 1)">;<br> </span><span style="color: rgba(0, 0, 255, 1)">for</span><span style="color: rgba(0, 0, 0, 1)">(</span><span style="color: rgba(0, 0, 255, 1)">var</span><span style="color: rgba(0, 0, 0, 1)"> count</span><span style="color: rgba(0, 0, 0, 1)">=</span><span style="color: rgba(0, 0, 0, 1)">0</span><span style="color: rgba(0, 0, 0, 1)">; count</span><span style="color: rgba(0, 0, 0, 1)"><</span><span style="color: rgba(0, 0, 0, 1)">len; count</span><span style="color: rgba(0, 0, 0, 1)">++</span><span style="color: rgba(0, 0, 0, 1)">){<br> name </span><span style="color: rgba(0, 0, 0, 1)">=</span><span style="color: rgba(0, 0, 0, 1)"> ch[count].nodeName;<br> }<br> </span><span style="color: rgba(0, 0, 255, 1)">return</span><span style="color: rgba(0, 0, 0, 1)"> name;<br> }<br></span><span style="color: rgba(0, 0, 255, 1)">function</span><span style="color: rgba(0, 0, 0, 1)"> testChildren(){<br> </span><span style="color: rgba(0, 0, 255, 1)">var</span><span style="color: rgba(0, 0, 0, 1)"> el </span><span style="color: rgba(0, 0, 0, 1)">=</span><span style="color: rgba(0, 0, 0, 1)"> $(</span><span style="color: rgba(0, 0, 0, 1)">'</span><span style="color: rgba(0, 0, 0, 1)">mydiv</span><span style="color: rgba(0, 0, 0, 1)">'</span><span style="color: rgba(0, 0, 0, 1)">),<br> ch </span><span style="color: rgba(0, 0, 0, 1)">=</span><span style="color: rgba(0, 0, 0, 1)"> el.children,<br> len </span><span style="color: rgba(0, 0, 0, 1)">=</span><span style="color: rgba(0, 0, 0, 1)"> ch.length,<br> name </span><span style="color: rgba(0, 0, 0, 1)">=</span><span style="color: rgba(0, 0, 0, 1)"> </span><span style="color: rgba(0, 0, 0, 1)">''</span><span style="color: rgba(0, 0, 0, 1)">;<br> </span><span style="color: rgba(0, 0, 255, 1)">for</span><span style="color: rgba(0, 0, 0, 1)">(</span><span style="color: rgba(0, 0, 255, 1)">var</span><span style="color: rgba(0, 0, 0, 1)"> count</span><span style="color: rgba(0, 0, 0, 1)">=</span><span style="color: rgba(0, 0, 0, 1)">0</span><span style="color: rgba(0, 0, 0, 1)">; count</span><span style="color: rgba(0, 0, 0, 1)"><</span><span style="color: rgba(0, 0, 0, 1)">len; count</span><span style="color: rgba(0, 0, 0, 1)">++</span><span style="color: rgba(0, 0, 0, 1)">){<br> name </span><span style="color: rgba(0, 0, 0, 1)">=</span><span style="color: rgba(0, 0, 0, 1)"> ch[count].nodeName;<br> }<br> </span><span style="color: rgba(0, 0, 255, 1)">return</span><span style="color: rgba(0, 0, 0, 1)"> name;<br> }</span> </div> </div> <p>正美：</p> <div><a>javascript测试函数运行速度</a></div> 相关文章： 2021-08-15 2021-07-22 2021-11-26 2021-06-18 2022-12-23 2022-12-23 2022-12-23 2022-12-23