vue 基础2(表单，自定义指令，计算属性，侦听器，过滤器的用法)
作者：互联网
1：表单的基本操作
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style type="text/css">
form div {
height: 40px;
line-height: 40px;
}
form div:nth-child(4) {
height: auto;
}
form div span:first-child {
display: inline-block;
width: 100px;
}
</style>
</head>
<body>
<div id="app">
<form action="http://itcast.cn">
<div>
<span>姓名：</span>
<span>
<input type="text" v-model='uname'>
</span>
</div>
<div>
<span>性别：</span>
<span>
<input type="radio" id="male" value="1" v-model='gender'>
<label for="male">男</label>
<input type="radio" id="female" value="2" v-model='gender'>
<label for="female">女</label>
</span>
</div>
<div>
<span>爱好：</span>
<input type="checkbox" id="ball" value="1" v-model='hobby'>
<label for="ball">篮球</label>
<input type="checkbox" id="sing" value="2" v-model='hobby'>
<label for="sing">唱歌</label>
<input type="checkbox" id="code" value="3" v-model='hobby'>
<label for="code">写代码</label>
</div>
<div>
<span>职业：</span>
<select v-model='occupation' multiple>
<option value="0">请选择职业...</option>
<option value="1">教师</option>
<option value="2">软件工程师</option>
<option value="3">律师</option>
</select>
</div>
<div>
<span>个人简介：</span>
<textarea v-model='desc'></textarea>
</div>
<div>
<input type="submit" value="提交" @click.prevent='handle'>
</div>
</form>
</div>
<script type="text/javascript" src="js/vue.js"></script>
<script type="text/javascript">
/*
表单基本操作
*/
var vm = new Vue({
el: '#app',
data: {
uname: 'lisi',
gender: 2,
hobby: ['2','3'],
// occupation: 3
occupation: ['2','3'],
desc: 'nihao'
},
methods: {
handle: function(){
// console.log(this.uname)
// console.log(this.gender)
// console.log(this.hobby.toString())
// console.log(this.occupation)
console.log(this.desc)
}
}
});
</script>
</body>
</html>
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2：表单修饰符的用法
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<div id="app">
<input type="text" v-model.number='age'>
<input type="text" v-model.trim='info'>
<input type="text" v-model.lazy='msg'>
<div>{{msg}}</div>
<button @click='handle'>点击</button>
</div>
<script type="text/javascript" src="js/vue.js"></script>
<script type="text/javascript">
/*
表单域修饰符
*/
var vm = new Vue({
el: '#app',
data: {
age: '',
info: '',
msg: ''
},
methods: {
handle: function(){
// console.log(this.age + 13)
// console.log(this.info.length)
}
}
});
</script>
</body>
</html>
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3：自定义指令的基本用法
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<div id="app">
<input type="text" v-focus>
<input type="text">
</div>
<script type="text/javascript" src="js/vue.js"></script>
<script type="text/javascript">
/*
自定义指令
*/
Vue.directive('focus', {
inserted: function(el){
// el表示指令所绑定的元素
el.focus();
}
});
var vm = new Vue({
el: '#app',
data: {
},
methods: {
handle: function(){
}
}
});
</script>
</body>
</html>
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4：带参数的自定义指令
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<div id="app">
<input type="text" v-color='msg'>
</div>
<script type="text/javascript" src="js/vue.js"></script>
<script type="text/javascript">
/*
自定义指令-带参数
*/
Vue.directive('color', {
bind: function(el, binding){
// 根据指令的参数设置背景色
// console.log(binding.value.color)
el.style.backgroundColor = binding.value.color;
}
});
var vm = new Vue({
el: '#app',
data: {
msg: {
color: 'blue'
}
},
methods: {
handle: function(){
}
}
});
</script>
</body>
</html>
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5：局部指令的用法
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<div id="app">
<input type="text" v-color='msg'>
<input type="text" v-focus>
</div>
<script type="text/javascript" src="js/vue.js"></script>
<script type="text/javascript">
/*
自定义指令-局部指令
*/
var vm = new Vue({
el: '#app',
data: {
msg: {
color: 'red'
}
},
methods: {
handle: function(){
}
},
directives: {
color: {
bind: function(el, binding){
el.style.backgroundColor = binding.value.color;
}
},
focus: {
inserted: function(el) {
el.focus();
}
}
}
});
</script>
</body>
</html>
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6：计算属性的基本用法
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<div id="app">
<div>{{msg}}</div>
<div>{{reverseString}}</div>
</div>
<script type="text/javascript" src="js/vue.js"></script>
<script type="text/javascript">
/*
计算属性
*/
var vm = new Vue({
el: '#app',
data: {
msg: 'Nihao'
},
computed: {
reverseString: function(){
return this.msg.split('').reverse().join('');
}
}
});
</script>
</body>
</html>
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7：计算属性与反方的区别
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<div id="app">
<div>{{reverseString}}</div>
<div>{{reverseString}}</div>
<div>{{reverseMessage()}}</div>
<div>{{reverseMessage()}}</div>
</div>
<script type="text/javascript" src="js/vue.js"></script>
<script type="text/javascript">
/*
计算属性与方法的区别:计算属性是基于依赖进行缓存的，而方法不缓存
*/
var vm = new Vue({
el: '#app',
data: {
msg: 'Nihao',
num: 100
},
methods: {
reverseMessage: function(){
console.log('methods')
return this.msg.split('').reverse().join('');
}
},
computed: { //依赖data中的数据做缓存，如果数据相同，多次调用执行一次，而方法不同
reverseString: function(){
console.log('computed')
// return this.msg.split('').reverse().join('');
var total = 0;
for(var i=0;i<=this.num;i++){
total += i;
}
return total;
}
}
});
</script>
</body>
</html>
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8：侦听器的基本用法
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<div id="app">
<div>
<span>名：</span>
<span>
<input type="text" v-model='firstName'>
</span>
</div>
<div>
<span>姓：</span>
<span>
<input type="text" v-model='lastName'>
</span>
</div>
<div>{{fullName}}</div>
</div>
<script type="text/javascript" src="js/vue.js"></script>
<script type="text/javascript">
/*
侦听器
*/
var vm = new Vue({
el: '#app',
data: {
firstName: 'Jim',
lastName: 'Green',
// fullName: 'Jim Green'
},
computed: {
fullName: function(){
return this.firstName + ' ' + this.lastName;
}
},
watch: {
// firstName: function(val) {
// this.fullName = val + ' ' + this.lastName;
// },
// lastName: function(val) {
// this.fullName = this.firstName + ' ' + val;
// }
}
});
</script>
</body>
</html>
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9：侦听器的案列
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<div id="app">
<div>
<span>用户名：</span>
<span>
<input type="text" v-model.lazy='uname'>
</span>
<span>{{tip}}</span>
</div>
</div>
<script type="text/javascript" src="js/vue.js"></script>
<script type="text/javascript">
/*
侦听器
1、采用侦听器监听用户名的变化
2、调用后台接口进行验证
3、根据验证的结果调整提示信息
*/
var vm = new Vue({
el: '#app',
data: {
uname: '',
tip: ''
},
methods: {
checkName: function(uname) {
// 调用接口，但是可以使用定时任务的方式模拟接口调用
var that = this;
setTimeout(function(){
// 模拟接口调用
if(uname == 'admin') {
that.tip = '用户名已经存在，请更换一个';
}else{
that.tip = '用户名可以使用';
}
}, 2000);
}
},
watch: {
uname: function(val){
// 调用后台接口验证用户名的合法性
this.checkName(val);
// 修改提示信息
this.tip = '正在验证...';
}
}
});
</script>
</body>
</html>
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10：过滤器的基本用法
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<div id="app">
<input type="text" v-model='msg'>
<div>{{msg | upper}}</div>
<div>{{msg | upper | lower}}</div>
<div :abc='msg | upper'>测试数据</div>
</div>
<script type="text/javascript" src="js/vue.js"></script>
<script type="text/javascript">
/*
过滤器
1、可以用与插值表达式和属性绑定
2、支持级联操作
*/
// Vue.filter('upper', function(val) {
// return val.charAt(0).toUpperCase() + val.slice(1);
// });
Vue.filter('lower', function(val) {
return val.charAt(0).toLowerCase() + val.slice(1);
});
var vm = new Vue({
el: '#app',
data: {
msg: ''
},
filters: {
upper: function(val) {
return val.charAt(0).toUpperCase() + val.slice(1);
}
}
});
</script>
</body>
</html>
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11：实例的生命周期
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<div id="app">
<div>{{msg}}</div>
<button @click='update'>更新</button>
<button @click='destroy'>销毁</button>
</div>
<script type="text/javascript" src="js/vue.js"></script>
<script type="text/javascript">
/*
Vue实例的生命周期
*/
var vm = new Vue({
el: '#app',
data: {
msg: '生命周期'
},
methods: {
update: function(){
this.msg = 'hello';
},
destroy: function(){
this.$destroy();
}
},
beforeCreate: function(){
console.log('beforeCreate');
},
created: function(){
console.log('created');
},
beforeMount: function(){
console.log('beforeMount');
},
mounted: function(){
console.log('mounted');
},
beforeUpdate: function(){
console.log('beforeUpdate');
},
updated: function(){
console.log('updated');
},
beforeDestroy: function(){
console.log('beforeDestroy');
},
destroyed: function(){
console.log('destroyed');
}
});
</script>
</body>
</html>
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12：变异方法和替换数组
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<div id="app">
<div>
<span>
<input type="text" v-model='fname'>
<button @click='add'>添加</button>
<button @click='del'>删除</button>
<button @click='change'>替换</button>
</span>
</div>
<ul>
<li :key='index' v-for='(item,index) in list'>{{item}}</li>
</ul>
</div>
<script type="text/javascript" src="js/vue.js"></script>
<script type="text/javascript">
/*
Vue数组操作
1、变异方法：会影响数组的原始数据的变化。
2、替换数组：不会影响原始的数组数据，而是形成一个新的数组。
*/
var vm = new Vue({
el: '#app',
data: {
fname: '',
list: ['apple','orange','banana']
},
methods: {
add: function(){
this.list.push(this.fname);
},
del: function(){
this.list.pop();
},
change: function(){
this.list = this.list.slice(0,2);
}
}
});
</script>
</body>
</html>
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13：动态响应是数据处理
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<div id="app">
<ul>
<li v-for='item in list'>{{item}}</li>
</ul>
<div>
<div>{{info.name}}</div>
<div>{{info.age}}</div>
<div>{{info.gender}}</div>
</div>
</div>
<script type="text/javascript" src="js/vue.js"></script>
<script type="text/javascript">
/*
动态处理响应式数据
*/
var vm = new Vue({
el: '#app',
data: {
list: ['apple', 'orange', 'banana'],
info: {
name: 'lisi',
age: 12
}
},
});
// vm.list[1] = 'lemon';
// Vue.set(vm.list, 2, 'lemon');
vm.$set(vm.list, 1, 'lemon');
// vm.info.gender = 'male';
vm.$set(vm.info, 'gender', 'female');
</script>
</body>
</html>
View Code
标签：function,el,vue,console,log,自定义,vm,侦听器,Vue 来源： https://www.cnblogs.com/Live-up-to-your-youth/p/15034023.html