js DOM的几个常用方法

 1

1 <div id="div1">这是个测试</div>
2 <p class="acc">111</p>
3 <p class="dd">222</p>

  //js DOM的几个常用方法

 2     //document.getElementById,
 3     // document.getElementsByTagName,
 4     // document.getElementsByClassName,
 5     // getAttribute,
 6     // setAttribute
 7 
 8     var div1 = document.getElementById("div1").innerHTML;
 9     console.log(div1);//output:这是个测试
10 
11     var pars = document.getElementsByTagName("p");
12     for (var i = 0; i < pars.length; i++) {
13         var title = pars[i].getAttribute("class");
14         if (title) {
15             pars[i].setAttribute("class", "look");//修改class的值为look
16             console.log(pars[i].getAttribute("class"));//output:look
17         }
18     }
19 
20     var cls = document.getElementsByClassName("look");
21     for (i in cls) {
22         console.log(cls[i].innerHTML);//111,222
23     }