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<html> <head> <title>Introduction to the DOM</title> <script> //直到文档完全载入，我们才能操作 DOM window.onload = function(){ //查找所有的<li>元素，附以事件处理程序 var li = document.getElementsByTagName("li"); for ( var i = 0; i < li.length; i++ ) { //将鼠标移入事件处理程序附在<li>元素上， //该程序改变<li>背景颜色为蓝色 li[i].onmouseover = function() { this.style.backgroundColor = ‘blue‘; }; //将鼠标移出事件处理程序附在<li>元素上， //该程序将<li>的背景颜色改回白色 li[i].onmouseout = function() { this.style.backgroundColor = ‘white‘; }; } }; </script> </head> <body> <h1>Introduction to the DOM</h1> <p class="test">There are a number of reasons why the DOM is awesome, here are some:</p> <ul> <li id="everywhere">It can be found everywhere.</li> <li class="test">It‘s easy to use.</li> <li class="test">It can help you to find what you want, really quickly.</li> </ul> </body> </html>