JavaScript实现Tab标签页切换的最简便方式

转载请注明出处:http://www.cnblogs.com/-867259206/p/5664896.html

先说一下最土的一种方法:

Html:

        <div class="tab-head">
            <h2 id="tab1" onmouseover="changeTab1()" class="selected">1</h2>
            <h2 id="tab2" onmouseover="changeTab2()">2</h2>
            <h2 id="tab3" onmouseover="changeTab3()">3</h2>
        </div>
        <div class="tab-content">
            <div id="c1" class="show">content1</div>
            <div id="c2">content2</div>
            <div id="c3">content3</div>
        </div>

CSS:

            h2 {
                border-top: solid cornflowerblue 1px;
                border-left: solid cornflowerblue 1px;
                width: 50px;
                height: 25px;
                margin: 0;
                float: left;
                text-align: center;
            }
            
            .tab-content {
                border: solid cornflowerblue 1px;
                width: 152px;
                height: 100px;
            }
            
            .tab-content div{
                display: none;
            }
            
            .selected {
                background-color: cornflowerblue;
            }
            
            .tab-content .show{
                display: block;
            }

JS:

            var tab1 = document.getElementById('tab1'),
                tab2 = document.getElementById('tab2'),
                tab3 = document.getElementById('tab3'),
                c1 = document.getElementById('c1'),
                c2 = document.getElementById('c2'),
                c3 = document.getElementById('c3');

            function changeTab1() {
                tab1.className = 'selected';
                tab2.className = '';
                tab3.className = '';
                c1.className = 'show'
                c2.className = '';
                c3.className = '';
            }

            function changeTab2() {
                tab1.className = '';
                tab2.className = 'selected';
                tab3.className = '';
                c1.className = '';
                c2.className = 'show';
                c3.className = '';
            }

            function changeTab3() {
                tab1.className = '';
                tab2.className = '';
                tab3.className = 'selected';
                c1.className = ''
                c2.className = '';
                c3.className = 'show';
            }

效果:

JavaScript实现Tab标签页切换的最简便方式

实现Tab的切换,我们很容易想到的一种方式就是给每一个要控制的标签添加id,然后分别编写鼠标事件,使用id获取每个元素,精确地控制每个元素的样式。

这种方式的缺点显而易见,有几个元素就有几个id,每个tab都要编写function,里面的方法大同小异。要增加tab的话,还要增加id和function,代码冗余,不易扩展。

第二种较为高明些的方法是编写一个function,将每个元素的序号传进去。

Html:

        <div class="tab-head">
            <h2 onmouseover="changeTab(0)" class="selected">1</h2>
            <h2 onmouseover="changeTab(1)">2</h2>
            <h2 onmouseover="changeTab(2)">3</h2>
        </div>
        <div class="tab-content">
            <div class="show">content1</div>
            <div>content2</div>
            <div>content3</div>
        </div>

JS:

            var tabs = document.getElementsByClassName('tab-head')[0].getElementsByTagName('h2'),
                contents = document.getElementsByClassName('tab-content')[0].getElementsByTagName('div');

            function changeTab(index) {
                for(var i = 0, len = tabs.length; i < len; i++) {
                    if(i === index) {
                        tabs[i].className = 'selected';
                        contents[i].className = 'show';
                    }else{
tabs[i].className = ''; contents[i].className = '';
}
} }

这样就只要写一个function了,而且不需要id,但是还是要按照顺序传递参数。

第三种方式和第二种基本一样,只是参数传递的是this指针。

Html:

        <div class="tab-head">
            <h2 onmouseover="changeTab(this)" class="selected">1</h2>
            <h2 onmouseover="changeTab(this)">2</h2>
            <h2 onmouseover="changeTab(this)">3</h2>
        </div>
        <div class="tab-content">
            <div class="show">content1</div>
            <div>content2</div>
            <div>content3</div>
        </div>

JS:

            var tabs = document.getElementsByClassName('tab-head')[0].getElementsByTagName('h2'),
                contents = document.getElementsByClassName('tab-content')[0].getElementsByTagName('div');

            function changeTab(tab) {
                for(var i = 0, len = tabs.length; i < len; i++) {
                    if(tabs[i] === tab) {
                        tabs[i].className = 'selected';
                        contents[i].className = 'show';
                    } else {
                        tabs[i].className = '';
                        contents[i].className = '';
                    }
                }
            }

这种方式稍微方便一些,只要传递this指针,不用按照顺序传递序号,但这也不是最简便的方式。

最简便的一种:

第四种方式:

Html:

        <div class="tab-head">
            <h2 class="selected">1</h2>
            <h2>2</h2>
            <h2>3</h2>
        </div>
        <div class="tab-content">
            <div class="show">content1</div>
            <div>content2</div>
            <div>content3</div>
        </div>

JS:

            var tabs = document.getElementsByClassName('tab-head')[0].getElementsByTagName('h2'),
                contents = document.getElementsByClassName('tab-content')[0].getElementsByTagName('div');

            (function changeTab(tab) {
                for(var i = 0, len = tabs.length; i < len; i++) {
                    tabs[i].onmouseover = showTab;
                }
            })();

            function showTab() {
                for(var i = 0, len = tabs.length; i < len; i++) {
                    if(tabs[i] === this) {
                        tabs[i].className = 'selected';
                        contents[i].className = 'show';
                    } else {
                        tabs[i].className = '';
                        contents[i].className = '';
                    }
                }
            }

这样JS、Html、CSS就完全分离了,通过this指针就可以判断当前鼠标滑过的是哪一个tab了。