如何在 static 方法中访问 object 值？

Question

I'm using static getDerivedStateFromProps from react to conditionally update the state.

This is the sample code:

static getDerivedStateFromProps(nextProps, prevState) {
        console.log(nextProps, prevState);
        if (prevState.web_data !== nextProps) {
            var data = nextProps.data;
            data.sort((a, b) => new Date(b.created) - new Date(a.created));
            console.log(data[0]);
            // nextProps.getData({data[0].website_id});
            return {
                web_data: data,
                // selected_web_id: data[0].website_id
            }
        }
        else {
            return null;
        }
    }

In the above code console.log(data[0]) returns the value of data at index 0 but when I try to access the object value inside the data[0] it throws error website_id is undefined.

The structure of data array is:

data = [{key:value, website_id...}, {key:value, website_id...}, {key:value, website_id...}, {key:value, website_id...}]

Answer 1

I suggest instead of using console.log() to figure out the error try using the debugger and trace each step to find out why it is undefined.

According to me earlier the props are empty and that's why you are not able to access the object property.