Use of the local storage localstorage and its encapsulated interface Store.js

localstorageHTML5 is a 客户端 new method of storing data that is stored in the client, and the data is 永久保存 , unless human intervention is removed.

localstorageUsed as local storage solves the problem of cookie insufficient storage space: Each cookie has a storage space of cookie 4k, but localStorage the storage space is 5 m in size. In addition, compared to cookies localStorage , 节约带宽 in the same domain, every time the browser sends a request to the server, HTTP will take a cookie, allowing the cookie to be passed back and forth between the browser and the server, wasting bandwidth, However, Localstorage stores the data of the first request directly to the local and avoids passing back and forth.

The limitations of Localstorage1, only the higher version of the browser is supported Localstorage2. The type of the Localstorage value is limited to type string, and JSON conversion is required when used3, if the storage of excessive content will consume memory space, resulting in the page card, because Localstorage is essentially a string read

There are two ways of Localstorage: the localstorage and sessionStorage . sessionStoragemethod 针对一个 session for data storage. When the user closes the browser window, the data is deleted. The only difference between Localstorage and Sessionstorage is that localstorage belongs to persistent storage, and sessionstorage key-value pairs in sessionstorage are emptied when the session ends.

The use of LocalstorageWhen we use localstorage, we need to first determine whether the browser supports localstorage this property:

The next is its write, read, delete

Use the key () method to get the corresponding key