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Handle error when localStorage value is not JSON parseable
See original GitHub issueIf a localStorage value is manually set (not through the hook) and is not valid JSON syntax, this library will throw an error when attempting to parse it:
Uncaught SyntaxError: Unexpected token a in JSON at position 0
Ideally, the hook should handle this error gracefully, in the case that another piece of code overrides the value or it is edited manually through dev tools.
Places to error check:
Issue Analytics
- State:
- Created 3 years ago
- Reactions:1
- Comments:13 (9 by maintainers)
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JSON.parse throwing error for invalid JSON not handled #98
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your solution is just fine, if you want it to be shorter, you could try this let resp = JSON.parse(localStorage.getItem('someKey') || null).
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I’ve encountered this. When you’re not following your good advise on namespacing keys, it’s possible (and potentially likely) that you may be using a key that some other app might also be using. In this case, their data may not be JSON and thus crash.
The obvious solution to this is to use namespaced keys, but having a way to gracefully recover would be nice. Maybe use the default value and do a
console.warn?I have thought a lot about this. I decided to put everything in place so the library doesn’t throw any errors. The new 5.1.0 release includes everything needed. Hope you like the change. Thanks to everybody who shared your opinion.
I am closing this issue now.