无法从JSON访问值

Question

I have this JSON string:

{
    "attachedFiles": [{
        "link": "/site.com/dir?id=12993&SESSION=40af90dd-c1f3-4678-93e5-a4b36f3597b0&SESSIONTICKET=SESS:67bf209be2",
        "fileName": "file1.txt",
        "docDate": "24.02.2014",
        "docTime": "13:54",
        "docId": "12993"
    }],
    "requestId": 48,
    "tasksId": 0,
    "workId": 10558
}

I'm converting it like this:

var resdata = xhr.responseText; // the string response from the server
var resObj = JSON.parse(resdata);

And then I'm trying to access(print the value) fileName inside of the attachedFiles object by the code below:

console.log(resObj.attachedFiles.fileName);

It always returns undefined . I know that I'm mising something real small here, but I'm not able to spot it.

Answer 1

attachedFiles is array. So try access the array content using indexer

resObj.attachedFiles[0].fileName // 0th index, 1st Element

To access all elements in the array. Thanks to @Cerbus comment

for(var i = 0, l = resObj.attachedFiles.length; i < l;i++)
{
   console.log(resObj.attachedFiles[i].fileName);
}

Answer 2

attachedFiles是一个array因此使用indexer是从零开始的索引，因此第一个元素将位于零索引。

console.log(resObj.attachedFiles[0].fileName);