如何在 ReactJS 中获取 ajax 数据

Question

I am building ontop of a ReactJS embedable web ui script as I am new to ReactJS. Here I am trying to pull data from my server and trying to display in the web ui. The problem I am facing is with the data that is coming from server as I am unable to parse it. Please find the data format below:

0: Object { name: "{\"draw\":0,\"recordsTotal\":8,\"recordsFiltered\":8,\"data\":[{\"first_name\":\"John\",\"last_name\":\"taylor\"},
{\"first_name\":\"John1\",\"last_name\":\"taylor1\"}]}" }
​
1: Object { school: "{\"draw\":0,\"recordsTotal\":0,\"recordsFiltered\":0,\"data\":
[{\"name\":\"school1\",\"location\":\"location1\"},
{\"name\":\"school2\",\"location\":\"location2\"}]}" }

PS: I cannot change my server data format.

Model code (model.ts)

export interface NameModel {
    name: object;
}

Form code (form.tsx)

const Name = () => {
    const service = useContext(ServiceContext);
    const [name, setName] = useState<NameModel[] | undefined>(undefined);
    const [visible, setVisible] = useState(0);
    const [statusText, setStatusText] = useState('');

    const loaders = [useTimeout(() => !name && setStatusText('Loading...'), 500)];

    useEffect(() => {
        service?.getName()
            .then(setName)
            .catch(() => setStatusText('Failed to load, try again later.'))
            .then(() => loaders.forEach((c) => c()));
    }, [service]);

    return (
        <div>
            {
                !name
                    ? statusText
                    : <Fragment>
                        <ul className={style.root}>
                            {
                                name.map((q, i) => (
                                {q}
                                    ))
                            }
                        </ul>
                    </Fragment>
            }
        </div>
    );
};

The above code produces: Uncaught (in promise) TypeError: name.map is not a function

How do I display the first_name and last_name from the first object that is sent from my server?

Thanks

Answer 1

Your issue is that name can be undefined by default, causing the name.map((q... part of the code to error because undefined doesn't have a map function.

You can fix this by changing to a more sensible default of empty array:

const [name, setName] = useState<NameModel[]>([]);