AngularJS provides filters to transform data:
- currency Format a number to a currency format.
- date Format a date to a specified format.
- filter Select a subset of items from an array.
- json Format an object to a JSON string.
- limitTo Limits an array/string, into a specified number of elements/characters.
- lowercase Format a string to lower case.
- number Format a number to a string.
- orderBy Orders an array by an expression.
- uppercase Format a string to upper case.
Examples
uppercase
<div ng-app="myApp" ng-controller="personCtrl">
<p>The name is {{ lastName | uppercase }}</p>
</div>
lowercase
<div ng-app="myApp" ng-controller="personCtrl">
<p>The name is {{ lastName | lowercase }}</p>
</div>
Adding Filters to Directives
Filters are added to directives, like ng-repeat, by using the pipe character |, followed by a filter:
Example
The orderBy filter sorts an array:
<div ng-app="myApp" ng-controller="namesCtrl">
<ul>
<li ng-repeat="x in names | orderBy:'country'">
{{ x.name + ', ' + x.country }}
</li>
</ul>
</div>
The currency Filter
The currency filter formats a number as currency:
Example
<div ng-app="myApp" ng-controller="costCtrl">
<h1>Price: {{ price | currency }}</h1>
</div>
The filter Filter
The filter filter selects a subset of an array.
The filter filter can only be used on arrays, and it returns an array containing only the matching items.
Example
Return the names that contains the letter “i”:
<div ng-app="myApp" ng-controller="namesCtrl">
<ul>
<li ng-repeat="x in names | filter : 'i'">
{{ x }}
</li>
</ul>
</div>
Filter an Array Based on User Input
<div ng-app="myApp" ng-controller="namesCtrl">
<p><input type="text" ng-model="test"></p>
<ul>
<li ng-repeat="x in names | filter : test">
{{ x }}
</li>
</ul>
</div>
Custom Filters
<ul ng-app="myApp" ng-controller="namesCtrl">
<li ng-repeat="x in names">
{{x | myFormat}}
</li>
</ul>
<script>
var app = angular.module('myApp', []);
app.filter('myFormat', function() {
return function(x) {
var i, c, txt = "";
for (i = 0; i < x.length; i++) {
c = x[i];
if (i % 2 == 0) {
c = c.toUpperCase();
}
txt += c;
}
return txt;
};
});
app.controller('namesCtrl', function($scope) {
$scope.names = ['Arun', 'Varun', 'James', 'John', 'Hari'];
});
</script>