AngularJS 霸道的过滤器小结

时间：2021-05-28

一、为什么使用过滤器？

在实际操作中，我们需要对统一数据源进行多次转换，比如我的货币单位，在不同的国家我们将用不同的符号表示。因此，你可能会想到在控制器中判断国家以显示不同的结果，但是过滤器却可以更好的帮助我们做到同样的效果。

过滤器将数据在被指令处理并显示到视图之前进行转换，而不必修改作用域中原有的数据，这样能够允许同一份数据在应用中的不同部分以不同形式得以展示。

接下来，我们详细讨论有关过滤器的用法

二、过滤单个数据的值

下表展示用于单个数据的内置过滤器

先来看看我们的准备案例，待会我们将在这个案例的基础上来使用内容过滤器

<!DOCTYPE><html ng-app="exampleApp"><head> <title>Angluar test</title> <meta charset="utf-8"/> <link rel="stylesheet" type="text/css" href="css/bootstrap.min.css" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" > <link rel="stylesheet" type="text/css" href="css/bootstrap-theme.min.css" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ></head><body> <dlv class="panel panel-default" ng-controller="defaultCtrl"> <div class="panel panel-header"> Products <span class="label label-primary">{{products.length}}</span> </div> <div class="panel panel-body"> <table class="table table-striped table-bordered table-hover"> <thead> <tr><th>Name</th><th>Category</th><th>Expiry</th><th>Price</th></tr> </thead> <tbody> <tr ng-repeat="p in products"> <td>{{p.name}}</td> <td>{{p.category}}</td> <td>{{p.expiry}}</td> <td>{{p.price}}</td> </tr> </tbody> </table> </div> </dlv><script type="text/javascript" src="js/angular.min.js"></script><script type="text/javascript">var myApp = angular.module("exampleApp", []);myApp.controller("defaultCtrl", function ($scope) { $scope.products = [ { name: "Apples", category: "Fruit", price: 1.20, expiry: 10 }, { name: "Bananas", category: "Fruit", price: 2.42, expiry: 7 }, { name: "Pears", category: "Fruit", price: 2.02, expiry: 6 }, { name: "Tuna", category: "Fish", price: 20.45, expiry: 3 }, { name: "Salmon", category: "Fish", price: 17.93, expiry: 2 }, { name: "Trout", category: "Fish", price: 12.93, expiry: 4 }, { name: "Beer", category: "Drinks", price: 2.99, expiry: 365 }, { name: "Wine", category: "Drinks", price: 8.99, expiry: 365 }, { name: "Whiskey", category: "Drinks", price: 45.99, expiry: 365 } ];})</script></body></html>

就是一个表格的形式来展示产品的详细情况的案例

1.格式化货币值

<tr ng-repeat="p in products"> <td>{{p.name}}</td> <td>{{p.category}}</td> <td>{{p.expiry}}</td>  <td>{{p.price | currency}}</td></tr>

2.格式化数字值

<tr ng-repeat="p in products"> <td>{{p.name}}</td> <td>{{p.category}}</td> <td>{{p.expiry}}</td>  <td>{{p.price | number : 3}}</td></tr>

3.格式化日期

// 在控制器中添加$scope.getExpiryDate = function (days) { var now = new Date(); return now.setDate(now.getDate() + days);}<tr ng-repeat="p in products"> <td>{{p.name}}</td> <td>{{p.category}}</td>  <td>{{getExpiryDate(p.expiry) | date : 'yyyy/MM/dd'}}</td>  <td>{{p.price}}</td></tr>

4.改变字符串大小写

<tr ng-repeat="p in products">  <td>{{p.name | uppercase}}</td> <td>{{p.category | lowercase}}</td> <td>{{getExpiryDate(p.expiry) | date : 'yyyy/MM/dd'}}</td>  <td>{{p.price}}</td></tr>

5.生成JSON

<tr ng-repeat="p in products">  <td>{{p.name | json}}</td> <td>{{p.category}}</td> <td>{{getExpiryDate(p.expiry) | date : 'yyyy/MM/dd'}}</td>  <td>{{p.price}}</td></tr>

6.本地化过滤器输出

需要移入本地化JS文件

<script type="text/javascript" src="js/angular-locale_zh-cn.js"></script><tr ng-repeat="p in products"> <td>{{p.name}}</td> <td>{{p.category}}</td> <td>{{p.expiry}}</td>  <td>{{p.price | currency}}</td></tr>

三、过滤集合

1.限制项目的数量—limitTo过滤器

<!DOCTYPE><html ng-app="exampleApp"><head> <title>Angluar test</title> <meta charset="utf-8"/> <link rel="stylesheet" type="text/css" href="css/bootstrap.min.css" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" > <link rel="stylesheet" type="text/css" href="css/bootstrap-theme.min.css" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ></head><body> <dlv class="panel panel-default" ng-controller="defaultCtrl"> <div class="panel panel-header"> Products <span class="label label-primary">{{products.length}}</span> </div> <div class="panel panel-body"> Limit: <select ng-model="limitVal" ng-options="item for item in limitRange"></select> </div> <div class="panel panel-body"> <table class="table table-striped table-bordered table-hover"> <thead> <tr><th>Name</th><th>Category</th><th>Expiry</th><th>Price</th></tr> </thead> <tbody>  <tr ng-repeat="p in products | limitTo : limitVal"> <td>{{p.name}}</td> <td>{{p.category}}</td> <td>{{p.expiry}}</td> <td>{{p.price | number : 2}}</td> </tr> </tbody> </table> </div> </dlv><script type="text/javascript" src="js/angular.min.js"></script><script type="text/javascript" src="js/angular-locale_zh-cn.js"></script><script type="text/javascript">var myApp = angular.module("exampleApp", []);myApp.controller("defaultCtrl", function ($scope) { $scope.products = [ { name: "Apples", category: "Fruit", price: 1.20, expiry: 10 }, { name: "Bananas", category: "Fruit", price: 2.42, expiry: 7 }, { name: "Pears", category: "Fruit", price: 2.02, expiry: 6 }, { name: "Tuna", category: "Fish", price: 20.45, expiry: 3 }, { name: "Salmon", category: "Fish", price: 17.93, expiry: 2 }, { name: "Trout", category: "Fish", price: 12.93, expiry: 4 }, { name: "Beer", category: "Drinks", price: 2.99, expiry: 365 }, { name: "Wine", category: "Drinks", price: 8.99, expiry: 365 }, { name: "Whiskey", category: "Drinks", price: 45.99, expiry: 365 } ]; // 显示的条数 $scope.limitVal = '5'; // 在限制条数的范围条项 $scope.limitRange = []; for (var i = (0 - $scope.products.length); i <= $scope.products.length; i++) { $scope.limitRange.push(i.toString()); }})</script></body></html>

单击下拉列表，根据提示显示不同的条数，负数表示从后往前取

2.选取项—filter过滤器

<!DOCTYPE><html ng-app="exampleApp"><head> <title>Angluar test</title> <meta charset="utf-8"/> <link rel="stylesheet" type="text/css" href="css/bootstrap.min.css" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" > <link rel="stylesheet" type="text/css" href="css/bootstrap-theme.min.css" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ></head><body> <dlv class="panel panel-default" ng-controller="defaultCtrl"> <div class="panel panel-header"> Products <span class="label label-primary">{{products.length}}</span> </div> <div class="panel panel-body"> <table class="table table-striped table-bordered table-hover"> <thead> <tr><th>Name</th><th>Category</th><th>Expiry</th><th>Price</th></tr> </thead> <tbody>  <tr ng-repeat="p in products | filter : selectItems"> <td>{{p.name}}</td> <td>{{p.category}}</td> <td>{{p.expiry}}</td> <td>{{p.price | number : 2}}</td> </tr> </tbody> </table> </div> </dlv><script type="text/javascript" src="js/angular.min.js"></script><script type="text/javascript" src="js/angular-locale_zh-cn.js"></script><script type="text/javascript">var myApp = angular.module("exampleApp", []);myApp.controller("defaultCtrl", function ($scope) { $scope.products = [ { name: "Apples", category: "Fruit", price: 1.20, expiry: 10 }, { name: "Bananas", category: "Fruit", price: 2.42, expiry: 7 }, { name: "Pears", category: "Fruit", price: 2.02, expiry: 6 }, { name: "Tuna", category: "Fish", price: 20.45, expiry: 3 }, { name: "Salmon", category: "Fish", price: 17.93, expiry: 2 }, { name: "Trout", category: "Fish", price: 12.93, expiry: 4 }, { name: "Beer", category: "Drinks", price: 2.99, expiry: 365 }, { name: "Wine", category: "Drinks", price: 8.99, expiry: 365 }, { name: "Whiskey", category: "Drinks", price: 45.99, expiry: 365 } ]; // 自定义过滤器 $scope.selectItems = function (item) { // 仅仅保留类别为Fish或者name=='Beer'的行 return item.category == 'Fish' || item.name == 'Beer'; }})</script></body></html>

仅仅保留类别为Fish或者name=='Beer'的行

3.对项目进行排序—orderBy过滤器

<!DOCTYPE><html ng-app="exampleApp"><head> <title>Angluar test</title> <meta charset="utf-8"/> <link rel="stylesheet" type="text/css" href="css/bootstrap.min.css" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" > <link rel="stylesheet" type="text/css" href="css/bootstrap-theme.min.css" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ></head><body> <dlv class="panel panel-default" ng-controller="defaultCtrl"> <div class="panel panel-header"> Products <span class="label label-primary">{{products.length}}</span> </div> <div class="panel panel-body"> <table class="table table-striped table-bordered table-hover"> <thead> <tr><th>Name</th><th>Category</th><th>Expiry</th><th>Price</th></tr> </thead> <tbody>        <tr ng-repeat="p in products | orderBy : [customOrder, '-price']"> <td>{{p.name}}</td> <td>{{p.category}}</td> <td>{{p.expiry}}</td> <td>{{p.price | number : 2}}</td> </tr> </tbody> </table> </div> </dlv><script type="text/javascript" src="js/angular.min.js"></script><script type="text/javascript" src="js/angular-locale_zh-cn.js"></script><script type="text/javascript">var myApp = angular.module("exampleApp", []);myApp.controller("defaultCtrl", function ($scope) { $scope.products = [ { name: "Apples", category: "Fruit", price: 1.20, expiry: 10 }, { name: "Bananas", category: "Fruit", price: 2.42, expiry: 7 }, { name: "Pears", category: "Fruit", price: 2.02, expiry: 6 }, { name: "Tuna", category: "Fish", price: 20.45, expiry: 3 }, { name: "Trout", category: "Fish", price: 12.93, expiry: 4 }, { name: "Salmon", category: "Fish", price: 17.93, expiry: 2 }, { name: "Beer", category: "Drinks", price: 2.99, expiry: 365 }, { name: "Wine", category: "Drinks", price: 8.99, expiry: 365 }, { name: "Whiskey", category: "Drinks", price: 45.99, expiry: 365 } ]; // 自定义函数排序 $scope.customOrder = function (item) { // 保质期<5的不排序，其他的按照价格升序排序 return item.expiry < 5 ? 0 : item.price; }})</script></body></html>

保质期<5的不排序，其他的按照价格升序排序

四、链式过滤器

就是将过滤器串联起来综合使用

<!DOCTYPE><html ng-app="exampleApp"><head> <title>Angluar test</title> <meta charset="utf-8"/> <link rel="stylesheet" type="text/css" href="css/bootstrap.min.css" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" > <link rel="stylesheet" type="text/css" href="css/bootstrap-theme.min.css" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ></head><body> <dlv class="panel panel-default" ng-controller="defaultCtrl"> <div class="panel panel-header"> Products <span class="label label-primary">{{products.length}}</span> </div> <div class="panel panel-body"> <table class="table table-striped table-bordered table-hover"> <thead> <tr><th>Name</th><th>Category</th><th>Expiry</th><th>Price</th></tr> </thead> <tbody>  <tr ng-repeat="p in products | orderBy : [customOrder, '-price'] | limitTo : 5"> <td>{{p.name}}</td> <td>{{p.category}}</td> <td>{{p.expiry}}</td> <td>{{p.price | number : 2}}</td> </tr> </tbody> </table> </div> </dlv><script type="text/javascript" src="js/angular.min.js"></script><script type="text/javascript" src="js/angular-locale_zh-cn.js"></script><script type="text/javascript">var myApp = angular.module("exampleApp", []);myApp.controller("defaultCtrl", function ($scope) { $scope.products = [ { name: "Apples", category: "Fruit", price: 1.20, expiry: 10 }, { name: "Bananas", category: "Fruit", price: 2.42, expiry: 7 }, { name: "Pears", category: "Fruit", price: 2.02, expiry: 6 }, { name: "Tuna", category: "Fish", price: 20.45, expiry: 3 }, { name: "Trout", category: "Fish", price: 12.93, expiry: 4 }, { name: "Salmon", category: "Fish", price: 17.93, expiry: 2 }, { name: "Beer", category: "Drinks", price: 2.99, expiry: 365 }, { name: "Wine", category: "Drinks", price: 8.99, expiry: 365 }, { name: "Whiskey", category: "Drinks", price: 45.99, expiry: 365 } ]; // 自定义函数排序 $scope.customOrder = function (item) { // 保质期<5的不排序，其他的按照价格升序排序 return item.expiry < 5 ? 0 : item.price; }})</script></body></html>

先按照自定义customOrder函数以price倒序排列，然后只取得5条数据

五、自定义过滤器

1.创建格式化数据值的过滤器

<!DOCTYPE><html ng-app="exampleApp"><head> <title>Angluar test</title> <meta charset="utf-8"/> <link rel="stylesheet" type="text/css" href="css/bootstrap.min.css" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" > <link rel="stylesheet" type="text/css" href="css/bootstrap-theme.min.css" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ></head><body> <dlv class="panel panel-default" ng-controller="defaultCtrl"> <div class="panel panel-header"> Products <span class="label label-primary">{{products.length}}</span> </div> <div class="panel panel-body"> <table class="table table-striped table-bordered table-hover"> <thead> <tr><th>Name</th><th>Category</th><th>Expiry</th><th>Price</th></tr> </thead> <tbody> <tr ng-repeat="p in products">  <td>{{p.name | labelCase}}</td> <td>{{p.category | labelCase : true}}</td> <td>{{p.expiry}}</td> <td>{{p.price | number : 2}}</td> </tr> </tbody> </table> </div> </dlv><script type="text/javascript" src="js/angular.min.js"></script><script type="text/javascript">var myApp = angular.module("exampleApp", []);myApp.controller("defaultCtrl", function ($scope) { $scope.products = [ { name: "Apples", category: "Fruit", price: 1.20, expiry: 10 }, { name: "Bananas", category: "Fruit", price: 2.42, expiry: 7 }, { name: "Pears", category: "Fruit", price: 2.02, expiry: 6 }, { name: "Tuna", category: "Fish", price: 20.45, expiry: 3 }, { name: "Trout", category: "Fish", price: 12.93, expiry: 4 }, { name: "Salmon", category: "Fish", price: 17.93, expiry: 2 }, { name: "Beer", category: "Drinks", price: 2.99, expiry: 365 }, { name: "Wine", category: "Drinks", price: 8.99, expiry: 365 }, { name: "Whiskey", category: "Drinks", price: 45.99, expiry: 365 } ];});</script><script type="text/javascript" src="js/createFilters.js"></script></body></html>

自定义过滤器，labelCase反转字符串

// js/createFilters.js文件angular.module("exampleApp") .filter("labelCase", function () { return function (value, reverse) { if (angular.isString(value)) { var inter = reverse ? value.toUpperCase() : value.toLowerCase(); return (reverse ? inter[0].toLowerCase() : inter[0].toUpperCase()) + inter.substr(1); } else { return value; } } })

2.创建集合过滤器

在createFilter中定义一个skip过滤函数

在视图中使用

<tr ng-repeat="p in products | skip : 2">  <td>{{p.name | labelCase}}</td> <td>{{p.category | labelCase : true}}</td> <td>{{p.expiry}}</td> <td>{{p.price | number : 2}}</td></tr>

移除前两项Apples和Bananas，然后显示

3.在已有的过滤器上搭建新的过滤器

在createFilter中添加take过滤器返回，将skip和limitTo两个过滤器方法综合起来

angular.module("exampleApp") .filter("labelCase", function () { return function (value, reverse) { if (angular.isString(value)) { var inter = reverse ? value.toUpperCase() : value.toLowerCase(); return (reverse ? inter[0].toLowerCase() : inter[0].toUpperCase()) + inter.substr(1); } else { return value; } } }) .filter("skip", function () { return function (value, count) { if (angular.isArray(value) && angular.isNumber(count)){ if (count > value.length || count < 0) { return value; } else { // 跳过数组前两项 return value.slice(count); } } else { return value; } } }) // 在已有过滤器的基础上建立新的过滤器 // 将上述的skip和limit两个过滤器合并 .filter("take", function ($filter) { return function (data, skipCount, limitCount) { // 先跳过数组的前skipCount项 var skipData = $filter("skip")(data, skipCount); // 接着只取limitCount行 return $filter("limitTo")(skipData, limitCount); } })

在视图中使用：

<tr ng-repeat="p in products | take : 2 : 5"> <td>{{p.name | labelCase}}</td> <td>{{p.category | labelCase : true}}</td> <td>{{p.expiry}}</td> <td>{{p.price | number : 2}}</td></tr>

先移除两项，然后值取5条数据

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。

AngularJS 霸道的过滤器小结

相关文章

AngularJS 过滤器的简单实例

AngularJS的内置过滤器详解

使用AngularJS创建自定义的过滤器的方法

Angularjs过滤器实现动态搜索与排序功能示例

angularjs自定义过滤器demo示例