Intro to coding and software development.
Native client applications have space for storage easily allocated. Cookies were one of the first implementations of local storage for web applications but they store very small bits of data. They are included in every HTTP request and that slows things down, and it isn’t encrypted, and are limited to 4kb.
IE had a larger userdata storage allocation. No one uses IE anymore. Flash allowed ‘flash cookies’ which were 100kb objects, one per domain. We don’t use Flash anymore. A browser plugin Gears gave space for SQL tables… every method relies on a platform specific or third party plugin.
HTML5 Storage allows for storing data of key/value pairs locally within the web browser that persists after navigating away from the page. The first step of utilizing it is to check if the browser supports it, as below function.
function supports_html5_storage() {
try {
return 'localStorage' in window && window['localStorage'] !== null;
} catch (e) {
return false;
}
}
We store key/value pairs. the key is a string, the value is any data type in javascript, but it’s stored as a string, so retrieval needs to use functions like parseInt(). It requires:
var foo = localStorage.getItem("bar"); //and respectively
localStorage.setItem("bar",foo);
Tracking changes to local storage requires listening for an event that fires when something is changed. Each origin gets 5mb of storage space. In the future SQL-like commands may be able to be used through javascript.