How Can I Keep JavaScript Variable Values After a Page Refresh?

Maintaining JS Variable Values After Page Refresh

Maintaining JavaScript variable values across page refreshes is essential for dynamic web applications and preserving user-specific information. To achieve this, we need to leverage web storage mechanisms that persist data even when the page is reloaded.

One powerful tool is localStorage, which allows you to permanently store data in the browser for the entire website. This is advantageous if you want to retain information across multiple sessions. To set a value using localStorage, use:

window.localStorage.setItem("variableName", value);

To retrieve the value, simply use:

let retrievedValue = window.localStorage.getItem("variableName");

Alternatively, if you need to store data that will only be preserved within the current browser session, you can use sessionStorage. The syntax is similar to localStorage, but sessionStorage will clear data when the browser window is closed.

window.sessionStorage.setItem("variableName", value);
let retrievedValue = window.sessionStorage.getItem("variableName");

It's important to note that only string values can be stored directly in these mechanisms. To store other data types, consider using JSON.stringify() and JSON.parse() for conversion.

For more in-depth information and workarounds for browsers that don't support localStorage, refer to the following resources:

• [MDN's DOM Storage Guide](https://developer.mozilla.org/en-US/docs/Web/Guide/API/DOM/Storage)
• [localStorage](https://developer.mozilla.org/en-US/docs/DOM/Storage#localStorage)
• [JSON](https://developer.mozilla.org/en-US/docs/JSON)
• [Browser Storage Compatibility](http://caniuse.com/namevalue-storage)

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