Question

I have JSON array with one object consisting of nodes and links.

data = [Object]=[ { nodes: Array[..] ,links: Array[…] } ]

This is all fine, but for accessing the links for example I have to use data[0].links, which is a bit annoying. I would like the array to be an object, so that data.links gives access to the links. I have tried to set:

data = data[0];

But then the array of Objects, data.links, are displayed as “undefined”.It seems like when a specific element is accessed the value is displayed, for example data.links[3].name. Why is that?

Edit:

More specifically:

if data = [ { nodes: Array[… ] ,links: Array[…] } ] =>

console.log(data[0].links); //shows the data[0].links[0].name = value in the console

if data = { nodes: Array[… ] ,links: Array[…] } =>

console.log(data.links); //shows data[0].links[0].name = undefined

but interestingly

console.log(data.links[0].name); //shows the correct value.

Answer 1

A couple of solutions:

If you control the JSON output, simply remove the enclosing brackets [] those are basically wrapping your object in an array.

data = { nodes: [...] ,links: [...] };

If you don’t control the JSON just simply assign the zero index of the array to the variable you actually want to work with.

json = [ { nodes: [...] ,links: [...] } ];
data = json[0];

Unfortunately, ‘links’ is an array. To access a member of that array, you will need to access its index value.