使用括号符号访问对象中的属性

Question

I'm using an ajax call through javascript and returning json.

I'm accessing the data using bracket notation because the object name had spaces, so I couldn't use dot notation.

This is the success function of my ajax call(not putting in the whole ajax call because of the API key).

success: function(data){
     console.log(data); 
     console.log(data['Time Series (1min)']);
},

I want the last property in the long list of properties in the "Time Series (1min)" object. I can't call it by key/property name as every minute, the property name changes (the data is minute-by-minute). I haven't found anything so far to help me online. I've tried .last() but dot notation and brackets don't seem to jive. Any ideas?

Answer 1

Once you got the data:

const series = data['Time Series (1min)'];

Just take all the keys and get the one with the highest timestamp:

const last = Object.keys(series).reduce((a, b) => a > b ? a : b);

Now that weve got the highest key, its easy:

console.log(series[last]);

All that is necessary cause object key order is not guaranteed, so you may switch over to using an array or a Map.

Answer 2

I assume that you simply want to get value of the last property of the object. (Based on this topic, object properties are sorted)

What about simpler:

data[Object.keys(data).pop()]

//Edit:

First of all you want to get "Time Series" property (which changes minute by minute), so maybe you want something like this:

data[Object.keys(data).find(key => key.match(/Time Series \(\d+min\)/))]

This will get value of time zone property in your scheme (object with dates). And - as I see - data that you receive is sorted by datetime, you can get object you are interested in by running code I've written in not edited post.