vue filter的四种用法
本章主要讲vue2的过滤器的使用
先介绍下vue1与vue2的filter区别，也就是vue2更新的地方
a: 2.0将1.0所有自带的过滤器都删除了，也就是说，在2.0中，要使用过滤器，则需要我们自己编写。
b: 2.0过滤器的传参方式不是以前的方式，是以函数传参的方式，下面示例（后面有具体示例）：
之前调用: {{msg | mimi '12' '5'}}
现在调用: {{msg | mimi('12','5')}}
c: 移除双向过滤器：
Vue.filter('change', {
read: function (val) {
return val
},
write: function (val, oldVal) {
return isEmail(val) ? val : oldVal
}
})
1.组件内部过滤（此例子写法适用于处理数据显示的样式，不会改变原数据）
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>filter</title>
<script src="https://unpkg.com/vue/dist/vue.js"></script>
</head>
<body>
<div id="app">
<ul>
<!--添加两个过滤器,注意不要冲突,注意先后顺序-->
<li v-for="item in list">{{item.id | filterAdd1 | filterAdd2}}</li>
</ul>
</div>
</body>
<script>
var vm = new Vue({
el:'#app',
data(){
return {
list:[
{"id":0,"title":"11111","cont":"111111"},
{"id":1,"title":"22222","cont":"111111"},
{"id":2,"title":"33333","cont":"111111"},
{"id":3,"title":"44444","cont":"111111"},
]
}
},
filters:{
filterAdd1(item) {
return item+10;
},
filterAdd2(item) {
return '$'+item;
}
},
methods:{
},
mounted(){
}
})
</script>
</html>
2.注册在全局的fliter，filter传值，filter动态传值
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>filter</title>
<script src="https://unpkg.com/vue/dist/vue.js"></script>
</head>
<body>
<div id="app">
<ul>
<!--添加两个过滤器,注意不要冲突,注意先后顺序-->
<!-- 过滤传值，带引号的是字符串，不带是number,传的值可以动态绑定-->
<li v-for="item in list">{{item.id | filterAdd1(Number(input),20) | filterAdd2}}</li>
</ul>
<input type="text" placeholder="place" v-model="input">
</div>
</body>
<script>
Vue.filter('filterAdd1', function (value,one,two) {
return value+one+two;//默认第一个参数就是默认要过滤的那个值
})
Vue.filter('filterAdd2', function (value) {
return '$'+value;
})
var vm = new Vue({
el:'#app',
data(){
return {
input:5,
list:[
{"id":0,"title":"11111","cont":"111111"},
{"id":1,"title":"22222","cont":"111111"},
{"id":2,"title":"33333","cont":"111111"},
{"id":3,"title":"44444","cont":"111111"},
]
}
},
methods:{
},
mounted(){
}
})
</script>
</html>
结果：
3. 计算属性筛选，methods方法筛选
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
<!-- <script src="vue.js"></script> -->
<script src="https://unpkg.com/vue/dist/vue.js"></script>
</head>
<body>
<div id="app">
<div @click="addMore">加载更多</div>
<ul><li v-for="item in filterlist">{{item}}</li></ul>
<hr>
<ul><li v-for="item in filterlistFun()">{{item}}</li></ul>
</div>
</body>
<script>
var vm = new Vue({
el:'#app',
data(){
return {
size:5,
list:[
{"id":0,"title":"11111","cont":"111111"},
{"id":1,"title":"22222","cont":"111111"},
{"id":2,"title":"33333","cont":"111111"},
{"id":3,"title":"44444","cont":"111111"},
{"id":4,"title":"55555","cont":"55555"},
{"id":5,"title":"66666","cont":"66666"},
{"id":6,"title":"77777","cont":"77777"},
{"id":7,"title":"77777","cont":"88888"},
{"id":8,"title":"888888","cont":"999999"},
{"id":9,"title":"000000","cont":"99999"},
{"id":10,"title":"a88888","cont":"99999"},
{"id":11,"title":"a22222","cont":"111111"},
{"id":12,"title":"a33333","cont":"111111"},
{"id":13,"title":"a44444","cont":"111111"},
{"id":14,"title":"a55555","cont":"55555"},
{"id":15,"title":"a66666","cont":"66666"},
{"id":16,"title":"a77777","cont":"77777"},
{"id":17,"title":"a77777","cont":"88888"},
{"id":18,"title":"a888888","cont":"999999"},
{"id":19,"title":"a000000","cont":"99999"},
{"id":20,"title":"a88888","cont":"99999"}
]
}
},
computed: {
filterlist () {
let num=this.size;
return this.list.filter(function (number) {
return number.id < num
})
}
},
methods:{
filterlistFun(val){
let num=this.size;
return this.list.filter(function (number) {
return number.id < num
})
},
addMore(){
this.size+=5;
},
},
mounted(){
}
})
</script>
</html>
4.使用js中的迭代函数filter
实例一原文
var app5 = new Vue({
el: '#app5',
data: {
shoppingList: [
"Milk", "Donuts", "Cookies", "Chocolate", "Peanut Butter", "Pepto Bismol", "Pepto Bismol (Chocolate flavor)", "Pepto Bismol (Cookie flavor)"
],
key: ""
},
computed: {
filterShoppingList: function () {
// `this` points to the vm instance
var key = this.key;
var shoppingList = this.shoppingList;
//在使用filter时需要注意的是，前面调用的是需要使用filter的数组，而给filter函数传入的是数组中的每个item，也就是说filter里面的函数，是每个item要去做的，并将每个结果返回。
return shoppingList.filter(function (item) {
return item.toLowerCase().indexOf(key.toLowerCase()) != -1
});;
}
}
})
<ul>
Filter Key<input type="text" v-model="key">
<li v-for="item in filterShoppingList">
{{ item }}
</li>
</ul>
最终效果实现了根据关键字来过滤列表的功能。
其他的一些Js 迭代方法——filter()、map()、some()、every()、forEach()、lastIndexOf()、indexOf()
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版权声明：本文为CSDN博主「ruanhongbiao」的原创文章，遵循 CC 4.0 BY-SA 版权协议，转载请附上原文出处链接及本声明。
原文链接：https://blog.csdn.net/qappleh/java/article/details/89639948
