function validateEmail(email) {
    var re = /^([\w-]+(?:\.[\w-]+)*)@((?:[\w-]+\.)*\w[\w-]{0,66})\.([a-z]{2,6}(?:\.[a-z]{2})?)$/i;
    return re.test(email);
	}
	(function( $ ){
		 $.fn.multipleInput = function() {
			  return this.each(function() {
				   // list of email addresses as unordered list
				   $list = $('<ul/>');
				   // input
				   var $input = $('<input type="email" id="email_search" class="email_search multiemail"/>').keyup(function(event) { 
						if(event.which == 13 || event.which == 32 || event.which == 188) {                        
							 if(event.which==188){
							   var val = $(this).val().slice(0, -1);// remove space/comma from value
							 }
							 else{
							 var val = $(this).val(); // key press is space or comma                        
							 }                         
							 if(validateEmail(val)){
							 // append to list of emails with remove button
							 $list.append($('<li class="multipleInput-email"><span>' + val + '</span></li>')
								  .append($('<a href="#" class="multipleInput-close" title="Remove"><i class="glyphicon glyphicon-remove-sign"></i></a>')
									   .on('click', function(e) {
											$(this).parent().remove();
											e.preventDefault();
									   })
								  )
							 );
							 $(this).attr('placeholder', '');
							 // empty input
							 $(this).val('');
							  }
							  else{
								alert('Please enter valid email id, Thanks!');
							  }
						}
				   });
				   // container div
				   var $container = $('<div class="multipleInput-container" />').on('click', function() {
						$input.focus();
				   });
				   // insert elements into DOM
				   $container.append($list).append($input).insertAfter($(this));
				   return $(this).hide();
			  });
		 };
	})( jQuery );
	$('#recipient_email').multipleInput();