I've exhausted all possible combinations such as x.y, x['y'], x.y.z, x['y'].z in an attempt to access the value of an object within an array using its key name. Despite my efforts, I'm unable to retrieve the desired value. The data returned from the SQL query is as follows:
parseMissionData: {record: Array(1), code: 1}
code: 1
record: Array(1)
0: alt: 45
attribute: Array(6)
0: {name: "messageCode", value: "10"}
1: {name: "gpsFix", value: "2"}
2: {name: "autonomous", value: "0"}
3: {name: "lowBattery", value: "1"}
4: {name: "intervalChange", value: "30"}
5: {name: "resetDetected", value: "0"}
length: 6
__proto__: Array(0)
azimuth: 0
datetime: "2018-03-24T20:10:00.000Z"
devid: "300434060496300"
lat: 37.335394620895386
lon: -121.82005405426025
speed: 0
__proto__: Object
length: 1
__proto__: Array(0)
__proto__: Object
....
Since attributes might not be consistently ordered, assuming attribute[0] corresponds to 'messageCode' is not viable. My goal is to test the value of the 'messageCode' attribute and use it for further processing. Here are some attempts I've made:
response.record[i].attribute['messageCode']
response.record[i].attribute.message.value
response.record[i].attribute['messageCode'].value
Despite numerous iterations, I haven't been successful. Is there a direct method to access the 'messageCode' attribute without iterating through the array?
Update: Following Mathias247's suggestion, I revised the code:
function parseMissionData(response) {
console.log('parseMissionData: ', response);
var codeAttribute;
for (var i=0; i < response.record.length; i++)
codeAttribute = response.record[i].attribute.find(elem => elem.name == "messageCode");
console.log('messageCode: ', codeAttribute);
console.log('imei direct: ', response.record[i].devid);
}
The updated code allows me to retrieve the 'messageCode' value successfully, but unexpectedly, the reference to 'devid' (response.record[i].devid) has now broken and returns undefined! When I remove the find() function related to 'messageCode', the devid reference works again. I am perplexed by how referencing using find() can impact another reference that previously worked. Can someone help clarify this behavior?
messageCode: {name: "messageCode", value: "10"}
jquery.min.js:2 jQuery.Deferred exception: Cannot read property 'devid' of undefined TypeError: Cannot read property 'devid' of undefined
at parseMissionData (http://localhost:3000/js/controller.js:1036:67)
at Object.<anonymous> (http://localhost:3000/js/controller.js:1021:17)
at j (http://localhost:3000/js/jquery.min.js:2:29948)
at k (http://localhost:3000/js/jquery.min.js:2:30262) undefined
To add more confusion, switching the order of console logs results in varying outcomes:
function parseMissionData(response) {
console.log('parseMissionData: ', response);
var codeAttribute;
for (var i=0; i < response.record.length; i++)
console.log('imei direct: ', response.record[i].devid);
codeAttribute = response.record[i].attribute.find(elem => elem.name == "messageCode");
console.log('messageCode: ', codeAttribute);
}
If I first log response.record[i].devid, it displays correctly, but then 'codeAttribute' throws an error stating 'Cannot read property 'attribute' of undefined'. Reversing the logs reveals similar issues with different references. Clearly, I'm missing something critical here. Any insights would be greatly appreciated.