Phone number filter, removes special characters, removes spaces, returns "N/A" if no phone number. For US phone numbers only.

Phone Number Filter - Angular

//Example of how to use the filter

<span> {{vm.phone_number | phonenumber}}</span>

//Example of how to add the filter

(function() {
    'use strict';

    angular
      .module('app.core')
      .filter('phonenumber', function() {
    	    /*
    	    Format phonenumber as: c (xxx) xxx-xxxx
    	    	or as close as possible if phonenumber length is not 10
    	    	if c is not '1' (country code not USA), does not use country code
    	    */

    	    return function (number) {
    		    /*
    		    @param {Number | String} number - Number that will be formatted as telephone number
    		    Returns formatted number: (###) ###-####
    		    	if number.length < 4: ###
    		    	else if number.length < 7: (###) ###
    		    Does not handle country codes that are not '1' (USA)
    		    */
    		    
    		      //Removes special characters and spaces
              number = String(number).replace(/[^0-9]/g, "");

              /Returns N/A if no phone number is present
    	        if (!number) { return 'N/A'; }

    	        // Will return formattedNumber.
    	        // If phonenumber isn't longer than an area code, just show number
    	        var formattedNumber = number;

    			// if the first character is '1', strip it out and add it back
    			var c = (number[0] == '1') ? '1 ' : '';
    			number = number[0] == '1' ? number.slice(1) : number;

    			// # (###) ###-#### as c (area) front-end
    			var area = number.substring(0,3);
    			var front = number.substring(3, 6);
    			var end = number.substring(6, 10);

    			if (front) {
    				formattedNumber = (c + "(" + area + ") " + front);
    			}
    			if (end) {
    				formattedNumber += ("-" + end);
    			}
    			return formattedNumber;
    	    };
    	});
})();


//Credit to Alexandra Burke for original version

https://gist.github.com/aberke/042eef0f37dba1138f9e