JSFiddle - React, Tailwind, and code Playground

HTML

<div id="storage">
	<input type="text" id="mail" value=""/>
	<button class="store">store</button>
	<button id="reset">reset</button>
	<button id="show">show</button>
</div>

JavaScript

$(document).ready(function() {	
	var id = 1;
	var mail = "Mail";

	$(".store").on("click", function(){
	     var mailaddress = localStorage.getItem("mailaddress");
	     var obj = [];
	     if(mailaddress){
	         obj= JSON.parse(mailaddress);  
	     }
	     obj.push({"id":  id, "mail":mail});
	     localStorage.setItem("mailaddress",JSON.stringify(obj));
	 });

	$("#show").on("click", function(){
	    var item = JSON.parse(localStorage.getItem("mailaddress"));
	    alert(item);
	    console.log(item);
	});
	$('#reset').click(function(){
		localStorage.clear();
	});
});