Hey everyone, I've hit a weird snag in my React project. I have an array of objects, and while the array reports the correct `.length`, when I try to access the first element like `array[0]`, it just returns `undefined`. Here's a snippet of my code:
```javascript
const foundFetchedServiceTypes = foundFetchedService.types;
const isTypeExistInFetchedService = foundFetchedServiceTypes.find(
(t) => t.id === type.id
);
console.log({
foundFetchedServiceTypes,
foundFetchedServiceTypesLength: foundFetchedServiceTypes.length,
foundFetchedServiceTypes0Elt: foundFetchedServiceTypes[0],
});
foundService.types.push({ ...type, isInitial, value });
```
I've also attempted using `structuredClone(foundFetchedService)` and `JSON.parse(JSON.stringify(...))`, but the issue persists. For reference, the output I'm seeing is:
`foundFetchedServiceTypes: [{type: 1, id: 123}]`
`foundFetchedServiceTypesLength: 0,`
`foundFetchedServiceTypes0Elt: undefined`
4 Answers
It looks like a classic race condition. There's a chance that you're not waiting for `foundFetchedService.types` to be populated. Have you tried using a debugger to step through and see when values are actually set?
It seems like you're dealing with a live reference here. When you log an array or an object to the console, you're actually logging a pointer to the original data, not a snapshot. This means that if the array changes afterwards, your console output will reflect that change. So by the time you're checking the first element, it might already have updated or cleared out. Try logging the array in a different context or taking a static snapshot of the data!
Could `foundFetchedService` be coming from an async source? If that’s the case, your first log may be running before the data has actually been fetched. Make sure that you're waiting for the data to be fully loaded before trying to access it.
What exactly is `foundFetchedService.types` to start with? Understanding the structure of your data might help narrow down where the undefined value is coming from.
Related Questions
How To: Running Codex CLI on Windows with Azure OpenAI
Set Wordpress Featured Image Using Javascript
How To Fix PHP Random Being The Same
Why no WebP Support with Wordpress
Replace Wordpress Cron With Linux Cron
Customize Yoast Canonical URL Programmatically