filter过滤器（作用）
- 数据渲染/输出之前，先处理一下
- 参数
### 自定义过滤器
app.controller('名字',function(){
//controller代码
})
app.filter('名字',function(){
//filter代码
})
<!DOCTYPE html>
<html ng-app='test'>
<head>
<meta charset="utf-8">
<title>angular</title>
<meta name="viewport" content="width=device-width,initial-scale=1.0,
maximum-scale=1.0,minimum-scale=1.0,user-scalable=no">
<link rel="stylesheet" type="text/css" href="static/css/reset.css">
<script src="js/angular1.58.js" charset="utf-8"></script>
<script >
var app=angular.module('test',[])
app.controller('zhangsan',function($scope,$http){
$scope.arr=[
{name:'买镯子',num:3,price:15},
{name:'卖早餐',num:5,price:8},
{name:'请朋友吃饭',num:2,price:-243}
]
})
</script>
</head>
<body ng-controller='zhangsan'>
<ul>
<li ng-repeat='v in arr'>{{v.name}} ；数量:{{v.num}} 花费{{v.num*v.price|currency}}</li>
</ul>
</body>
</html>
