calling an array from another web page?

Question

I am building a website and can't understand how to pass arrays across different web pages of the same website. The code for defining the array is:

sessionStorage.setItem("hello", JSON.stringify(["hi", "sup"]));

The code for calling the array on the second page is:

var helloArray = JSON.parse(sessionStorage.getItem("hello"));

When I loop through the array with this code:

for (var i = 0; i < helloArray.length; i++) {
  // JavaScript code
}

It creates an error that says: Uncaught TypeError: Cannot read property 'length' of null.

What can I change and what did I do wrong?

Maybe you want localStorage instead? From the documentation: "This is a global object (sessionStorage) that maintains a storage area that's available for the duration of the page session. A page session lasts for as long as the browser is open and survives over page reloads and restores. Opening a page in a new tab or window will cause a new session to be initiated." — Felix Kling
– Felix Kling, Commented Nov 27, 2014 at 0:18
Sessions should really only be used to store strings. They're unreliable with other forms of information. Try storing it as a string and recovering it as a hash/JSON. — steel
– steel, Commented Nov 27, 2014 at 1:10

Winner Crespo · Accepted Answer · 2014-11-27 01:22:27Z

2

Use localStorage like this:

- To write content:

localStorage.setItem("hello", JSON.stringify(["hi", "sup"]));

- To read content:

var helloArray = JSON.parse(localStorage.getItem('hello'));

answered Nov 27, 2014 at 1:15

Winner Crespo

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