Web Storage API
The Web Storage API is a simple syntax for storing and retrieving data in the browser. It is very easy to use:
The Web Storage API is supported in all browsers:
| Chrome | IE/Edge | Firefox | Safari | Opera |
| Yes | Yes | Yes | Yes | Yes |
The localStorage Object
The localStorage object provides access to a local storage for a particular Web Site. It allows you to store, read, add, modify, and delete data items for that domain.
The data is stored with no expiration date, and will not be deleted when the browser is closed.
The data will be available for days, weeks, and years.
The setItem() Method
The localStorage.setItem() method stores a data item in a storage.
It takes a name and a value as parameters:
Example
localStorage.setItem("name", "John Doe");
The getItem() Method
The localStorage.getItem() method retrieves a data item from the storage.
It takes a name as parameter:
Example
localStorage.getItem("name");
The sessionStorage Object
The sessionStorage object is identical to the localStorage object.
The difference is that the sessionStorage object stores data for one session.
The data is deleted when the browser is closed.
The setItem() Method
The sessionStorage.setItem() method stores a data item in a storage.
It takes a name and a value as parameters:
Example
sessionStorage.setItem("name", "John Doe");
The getItem() Method
The sessionStorage.getItem() method retrieves a data item from the storage.
It takes a name as parameter:
Example
sessionStorage.getItem("name");
Storage Object Properties and Methods
| Property/Method | Description |
|---|---|
| key(n) | Returns the name of the nth key in the storage |
| length | Returns the number of data items stored in the Storage object |
| getItem(keyname) | Returns the value of the specified key name |
| setItem(keyname, value) | Adds a key to the storage, or updates a key value (if it already exists) |
| removeItem(keyname) | Removes that key from the storage |
| clear() | Empty all key out of the storage |
Related Pages for Web Storage API
| Property | Description |
|---|---|
| window.localStorage | Allows to save key/value pairs in a web browser. Stores the data with no expiration date |
| window.sessionStorage | Allows to save key/value pairs in a web browser. Stores the data for one session |