Get value from associative array with string

Question

I have a json response I'm getting from a server with different response structures.

One uses another value "data" to store a link:

and the other doesn't (with "image" being the link):

I was wondering if there was a way I can get the "data.link" from the associative array with a reusable method, with linkVariableName being the key of the associative array.

function addLink(responseText, successVariableName, isError, linkVariableName)
{
 var jsonResponse = JSON.parse(responseText);
 var state;
 if (isError)
 state = !jsonResponse[successVariableName];
 else
 state = jsonResponse[successVariableName];
 if (state) {
 var link = jsonResponse[linkVariableName];
 insertAtCursor(textArea, '[img]' + link + '[/img]\r\n');
 } else
 console.log('Error: ' + responseText);
}

so I can use either

addLink(response.responseText, 'success', false, 'data.link');

or

addLink(response.responseText, 'error', true, 'image');

• Felix Kling: How do you determine which parameters to the pass to the function?
• gcampbell: Note: JavaScript does not have associative arrays.
• Mr. Trvp: @gcampbell I'm use to associating json with associative arrays.

Answer 1

Yes you can, as explained here: Accessing nested JavaScript objects with string key

However, IMO the function tries to do too much. Why does it need to parse the JSON and extract the value? You could just pass the value directly to it:

function addLink(link) {
 insertAtCursor(textArea, '[img]' + link + '[/img]\r\n');
}

And move the other logic to where you handle the response:

var isError = ...;
var response = JSON.parse(responseText);
if (isError && !response.error) {
 addLink(response.image);
} else if(!isError && response.success) {
 addLink(response.data.link);
} else {
 console.log('Error: ' + responseText);
}

• Mr. Trvp: i.imgur.com/CxeKSpZ.gif It's quite cluttered as it is.. I figured putting everything in that method would make it a little more clear. Thank you for your solution.