测试localStorage / sessionStorage最大数据量

Question

I'm writing a page to test how much data localStorage and sessionStorage can save in the browser.

It works somewhat but the browser gets unresponsive and the process bar/text is not updated progressively but mostly all at onces at the end or when the unresponsive dialogbox apears.

One of the reasons for the unresponsiveness if when i create a really large string.

  blablaantal might be 1048576 to create a string with 1048576 x-charachers.

  data = '';

  for (i = 0; i < blablaantal; i++) {

     data += 'x';

  }

Code and Demo : http://netkoder.dk/netkoder/eksempler/eksempel0008.html

Answer 1

localStorage.remainingSpace will tell you how many bytes you can store.

EDIT: In a more general case, try this:

blablaantal = 1048576;
data = new Array(blablaantal+1).join("x");

Answer 2

Yeah, i played around a few years ago to see if i could find a safe, performant way to test this in all browsers. I didn't. The best i achieved at the time is here:

https://github.com/nbubna/store/blob/master/src/store.measure.js

as a plugin for my store2.js wrapper. It'll work faster than your method, but it will still crash/freeze things up sometimes. Though, i haven't tried in a few years, things may be better or, i suppose, worse.