vue自定义指令directives及全局自定义指令directive

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<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>p45-47:vue自定义指令</title>
    <script type="text/javascript" src="js/vue.js"></script>

</head>

<body>


<div id="demo">
    <p>{{website}}</p>
    <p>原来的n:<span>n={{n}}</span></p>
    <p>自定义指令-放大10倍:<span v-big="n"></span></p>
    <p>自定义指令-放大100倍:<span v-big1="n"></span></p>
    <button @click="n++">n++</button>
    <hr/>
    <input type="text" v-focusbind:value="n">
    <input type="text" v-focusbind1:value="n">
</div>
<script type="text/javascript">
    //全局自定义指令
    Vue.directive('focusbind1',{
        //绑定
        bind(element, binding) {
            console.log('bind')
            element.value = binding.value
        },
        //指令所在元素被插入页面
        inserted(element, binding) {
            console.log('insert')
            element.focus()

        },
        //指令所在元素被更新
        update(element, binding) {
            console.log('update')
            element.value = binding.value
        }
    });
    //全局自定义指令-function写法
    Vue.directive('big1',function(element,binding){
        console.log('big1被调用')
        element.innerText = binding.value * 100
    })

    //创建vue实例
    const vm = new Vue({
        el: "#demo",
        data: {
            n: 1,
            website: 'http://www.hu-rong.com'
        },
        methods: {},
        computed: {},
        watch: {},
        filters: {},
        directives: {
            /**
             *自定义指令
             * 指令与元素绑定(bind阶段)或指令所有模板被重新解析时会被调用(update阶段)，如修改website时也会导致big被调用
             */
            big(element, binding) {
                console.log('big被调用')
                element.innerText = binding.value * 10
            },
            // focusbind(element, binding) {
            //     //绑定自动获得焦点，但这里有个问题，首页绑定时是不会得到焦点的，因为页面上还没有这个元素
            //     element.value=binding.value
            //     element.focus()
            // }
            //要用完整写法实现这个生命周期的过程
            focusbind: {
                //绑定
                bind(element, binding) {
                    console.log('bind')
                    element.value = binding.value
                },
                //指令所在元素被插入页面
                inserted(element, binding) {
                    console.log('insert')
                    element.focus()

                },
                //指令所在元素被更新
                update(element, binding) {
                    console.log('update')
                    element.value = binding.value
                }
            }
        }
    })

</script>
</body>
</html>
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