check phone number

check if a number contain repeated numbers

HTML

<input type="text" id="phone" name="phone">
<button id="submit" type="submit">check</button>
<br><span id="result"></span>

TypeScript

$( document ).ready(function() {

$(document).on("click", "#submit", function() {
$('#result').empty();
	$('#result').append(checkPhone());
});
  
  var checkPhone = function(){
  
     phone_number = $('#phone').val();
     
     res = (/^(.)\1+$/.test(phone_number) ? '1' : '0');
    if(res == '1'){
    
    	return 'bad phone number';
    }else{
    	return 'good phone number';
    }
    	
  };
  
    
});