cookie
唯一优势是它们得到了非常旧的浏览器的支持，所以如果您的项目需要支持已经过时的浏览器（比如 Internet Explorer 8 或更早的浏览器）
document.cookie = “name=”+name
web storage —— 存储简单数据（IE8）
sessionStorage ：只要浏览器开着，数据就会一直保存 (关闭浏览器时数据会丢失)
localStorage ：会一直保存数据，甚至到浏览器关闭又开启后也是这样。
localStorage.setItem('name','Chris');localStorage.getItem('name');localStorage.removeItem('name');IndexedDB——存储复杂数据（IE10）
// Create an instance of a db object for us to store the open database in
let db;
window.onload = function() {
// Open our database; it is created if it doesn't already exist
// (see onupgradeneeded below)
let request = window.indexedDB.open('notes', 1);
// onerror handler signifies that the database didn't open successfully
request.onerror = function() {
console.log('Database failed to open');
};
// onsuccess handler signifies that the database opened successfully
request.onsuccess = function() {
console.log('Database opened successfully');
// Store the opened database object in the db variable. This is used a lot below
db = request.result;
// Run the displayData() function to display the notes already in the IDB
displayData();
};
// Setup the database tables if this has not already been done
request.onupgradeneeded = function(e) {
// Grab a reference to the opened database
let db = e.target.result;
// Create an objectStore to store our notes in (basically like a single table)
// including a auto-incrementing key
let objectStore = db.createObjectStore('notes', { keyPath: 'id', autoIncrement:true });
// Define what data items the objectStore will contain
objectStore.createIndex('title', 'title', { unique: false });
objectStore.createIndex('body', 'body', { unique: false });
console.log('Database setup complete');
};
};
离线文件存储——IE还不支持