用js怎么改变css样式(2)-木庄网络博客

例如：

1	`div1.setAttribute("href","css2.css");`

html代码：

<link href="css/css1.css" rel="stylesheet" id="cssLink" />
<div id="divBtn1" onclick="changeCss1()">1</div>
<div id="divBtn2" onclick="changeCss2()">2</div>
<div id="divBtn3" onclick="changeCss3()">3</div>
<div id="divBtn4" onclick="changeCss4()">4</div>

css1.css文件

@charset "utf-8";
#divBtn1,#divBtn2,#divBtn3,#divBtn4{
    width:100px;
    height:100px;
    margin-bottom: 10px;
}
#divBtn1{background:yellowgreen;}
#divBtn2{background:paleturquoise;}
#divBtn3{border:1px solid #ccc}
#divBtn4{background:blue;}
.div3{width:100px;height:100px;background:blueviolet}

css2.css文件

@charset "utf-8";
#divBtn4{background: greenyellow;}
#divBtn1,#divBtn2,#divBtn3,#divBtn4{
    width:200px;
    height:200px;
    border:1px solid #ccc;
    margin-bottom: 10px;
}
#divBtn1{background:yellowgreen;}
#divBtn2{background:paleturquoise;}
.div3{width:100px;height:100px;background:blueviolet}

js代码：

<script>
            /*
             *javascript动态修改css效果的方法（四种） 
             * 第一种：div1.style.width="100px";
             * 第二种：div2.style.cssText="width:100px;height:100px;background: palevioletred;";
             * 第三种：div1.setAttribute("class","div2")和div3.className="div3";//效果一样
             * 第四种：使用更改外联的css文件，从而改变元素的css
             * obj.setAttribute("href","css/css2.css");
             * */
            function changeCss1(){
                var div1=document.getElementById("divBtn1");
                div1.style.width="100px";
                div1.style.height="100px";
                div1.style.background="red";
            }
            function changeCss2(){
                var div2=document.getElementById("divBtn2");
                div2.style.cssText="width:100px;height:100px;background: palevioletred;";                //cssText会覆盖之前的设置  无兼容性问题  写法和css样式表相同
            }
            function changeCss3(){
                var div3=document.getElementById("divBtn3");                //div3.className="div3";//效果一样
                div3.setAttribute("class","div3");
            }
            function changeCss4(){
                var obj=document.getElementById("cssLink");
                obj.setAttribute("href","css/css2.css");
            }
        </script>