Local and Session Storage

Prototype functions to handle localStorage and sessionStorage.

by João Vicente Machado

HTML

<script src="https://code.jquery.com/jquery-2.2.4.js"></script>
<div>
<span id="myTextToStore">STORED TEXT</span>
</div>
<div>
<span id="myStoredText"></span>
</div>
<div>
<span id="remainingSpace">REMAINING SPACE IN KB</span>
</div>

JavaScript

Storage.prototype.setObject = function(key, value) {
    this.setItem(key, JSON.stringify(value));
}

Storage.prototype.getObject = function(key) {
    var value = this.getItem(key);
    return value && JSON.parse(value);
}

Storage.prototype.removeObject = function(key) {
    this.removeItem(key);
}

Storage.prototype.clearAll = function() {
    this.clear();
}

Storage.prototype.remainingSpace = function() {
		return (5101 - JSON.stringify(this).length);
}

// Usage examples:
//----------------
var myText = document.getElementById("myTextToStore").innerHTML; 
sessionStorage.setObject('textToStore', myText);

var anotherText = sessionStorage.getObject('myTextToStore');
document.getElementById("myStoredText").innerHTML=anotherText;

//localStorage.clearAll();
//sessionStorage.removeObject('myTextToStore');

var remaining = "REMAINING SPACE IN KB = " + sessionStorage.remainingSpace();
document.getElementById("remainingSpace").innerHTML=remaining;