code to set and get cookies in browser using javascript

cookies.js

/* ***************************************
 *          COOKIE STORAGE
 * 
 * Capacity: 4kb
 * Browser: HTML4/5
 * Accessible: From any window
 * Expires: Wll last as per number of days provided / Manual Set
 * Storage location: Browser and server
 * Sent with requests: Yes
 * *************************************** */

function writeCookie(name,value,days) {
    var date, expires;
    if (days) {
        date = new Date();
        date.setTime(date.getTime()+(days*24*60*60*1000));
        expires = "; expires=" + date.toGMTString();
            }else{
        expires = "";
    }
    document.cookie = name + "=" + value + expires + "; path=/";
}

function readCookie(name) {
    var i, c, ca, nameEQ = name + "=";
    ca = document.cookie.split(';');
    for(i=0;i < ca.length;i++) {
        c = ca[i];
        while (c.charAt(0)==' ') {
            c = c.substring(1,c.length);
        }
        if (c.indexOf(nameEQ) == 0) {
            return c.substring(nameEQ.length,c.length);
        }
    }
    return '';
}

function deleteAllCookies() {
    var cookies = document.cookie.split(";");

    for (var i = 0; i < cookies.length; i++) {
        var cookie = cookies[i];
        var eqPos = cookie.indexOf("=");
        var name = eqPos > -1 ? cookie.substr(0, eqPos) : cookie;
        document.cookie = name + "=;expires=Thu, 01 Jan 1970 00:00:00 GMT";
    }
}

// setting cookie value
var sId = 's234543245';
writeCookie('sessionId', sId, 3);

// getting cookie value
var sId = readCookie('sessionId');

localStorage.js

/* ***************************************
 *          LOCAL STORAGE
 * 
 * Capacity: 10 MB
 * Browser: HTML5
 * Accessible: From any window
 * Expires: Will last as long as you won't clear / Never
 * Storage location: Browser only
 * Sent with requests: No
 * *************************************** */

function getAllLocalData() {
    return window.localStorage;
}

function writeLocal(key, value) {
    if (localStorageCompatible() ) {
        localStorage.setItem(key, value);
        return true;
    } else {
        console.log('Browser not compatible, Please contact admin');
    }
}

function readLocal(key) {
    if (localStorageCompatible()) {
        return localStorage.getItem(key);
    } else {
        console.log('Browser not compatible, Please contact admin');
    }
}

function deleteLocal(key) {
    if (localStorageCompatible()) {
        localStorage.removeItem(key);
        return true;
    } else {
        console.log('Browser not compatible, Please contact admin');
    }
}

function clearLocal() {
    if (localStorageCompatible()) {
        window.localStorage.clear();
        return true;
    } else {
        console.log('Browser not compatible, Please contact admin');
    }
}

function localStorageCompatible() {
    if (typeof (Storage) !== "undefined")
        return true;
    return false;
}

sessionStorage.js

/* ***************************************
 *          SESSION STORAGE
 * 
 * Capacity: 10 MB
 * Browser: HTML5
 * Accessible: Same tab
 * Expires: will last as long as you don't close tab
 * Storage location: Browser only
 * Sent with requests: No
 * *************************************** */

function getAllSessionData() {
    return window.sessionStorage;
}

function writeSession(key, value) {
    if (sessionStorageCompatible()) {
        sessionStorage.setItem(key, value);
        return true;
    } else {
        console.log('Browser not compatible, Please contact admin');
    }
}

function readSession(key) {
    if (sessionStorageCompatible()) {
        return sessionStorage.getItem(key);
    } else {
        console.log('Browser not compatible, Please contact admin');
    }
}

function deleteSession(key) {
    if (sessionStorageCompatible()) {
        sessionStorage.removeItem(key);
        return true;
    } else {
        console.log('Browser not compatible, Please contact admin');
    }
}

function clearSession() {
    if (sessionStorageCompatible()) {
        window.sessionStorage.clear();
    } else {
        console.log('Browser not compatible, Please contact admin');
    }
}

function sessionStorageCompatible() {
    if (typeof (Storage) !== "undefined")
        return true;
    return false;
}