Angular js filter
Types of filters used in AngularJS are: 1) Currency, 2) Uppercase, 3) Lowercase, 4) orderBy, 5) JSON, and 6) limitTo.
The main work of filters is to modify the data, so that it can be merged into an expression or directive by using a pipe character (it is used for applying filters in an angular symbol of a pipe which is (|) or this is the symbol).
A filter formats the value of an expression for a display to the user. They can be used in view templates, controllers, or services, and we can easily create our own filter as well. A filter is a module provided by AngularJS. There are nine components of a filter which are provided by it.
Examples: currency, date, filter, JSON, limitTo, etc.
Currency, lowercase, uppercase, number, date are few inbuilt angular filters.
{{nameOfStudent|uppercase}}
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With AngularJS we can create our own filters. This can be done by associating the filter to our module. These types of filters are called custom filters.
Below is the code to count the number of elements in the string by using filter:
angular.module('myCountFilterApp', [])
.filter('count',function()
{
return(function(input)
{
var out=[];
out=input.split(',');
return out.length;
})
});
In the above example, if the string is "21, 34, 45" then output after applying filter will be 3.
Here is some more information on custom filters.
{{ Somevalue|lowercase|uppercase}}
Pipe operator in AngularJS represents filters that are used on the expression. The preference order is from left to right. So, the result of the above expression would be SOMEVALUE.
Angualr.JS filters are efficient in modifying the data. With the help of pipe (|) character, they are clubbed into the directive or expression.
Filters Functions
Uppercase It used to convert text to upper case text.
Lowercase It used to convert text to lower case text.
Currency It is used to formats a number to a currency format.
Order by It is used to orders the array on the basis of given criteria.
Filter It is used to order the array to a subset of it on the basis of given criteria.
An interceptor is a middleware code in AngularJs where all the $http requests go through. It is attached with $httpProvider service and able to intercept request and response objects. Interceptor Middleware is useful for error handling, authentication and other filters you want to apply on request and response.
$stateful filters are executed one or more times during each $Digest cycle. It is not recommended to write a $stateful filter in AngularJS.
One of the filters in AngularJS is the Currency Filter. This “currency” filter includes the “$” Dollar Symbol as the default. So we can use the following code as the html template format of Currency Filter.
{{ currency_expression | currency : symbol : fractionSize}}
Filters are used to modify the data and can be clubbed in expression or directives using a pipe character. A filter formats the value of an expression for display to the user. They can be used in view templates, controllers, or services, and we can easily create our own filter. Filter is a module provided by AngularJS. There are nine components of filter which are provided by AngularJS. We can write custom as well.
currency
date
filter
json
limitTo
lowercase
number
orderBy
uppercase
