I would like to map the object and get the number/length of replies that can be found in replies
in this case 2. I have fetched this data from the API and is unable to get the number of replies that can be found here.
let data = [
{
"feedbackId":32,
"sender":"12345"
"comment":"Test Comment",
"replies":[
{
"feedbackLogId":32,
"feedbackReplyLogId":1,
"comments":"So this is 1",
"createdBy":"Jack",
},
{
"feedbackLogId":32,
"feedbackReplyLogId":2,
"comments":"2nd one",
"createdBy":"Min",
}
],
}
]
This is what I've done. I am only able to get 1
as the length.
let repliesToRender = data.map((item) => {item.replies})
let numReplies = repliesToRender.length
You have 2 issue in your code,
let repliesToRender = data.map((item) => {item.replies})
should be
let repliesToRender = data.map((item) => item.replies)
And map return you array so your repliesToRender will be an array of array so you need
let numReplies = repliesToRender[0].length
Or just
let numReplies = data.replies.length
let data = [ { "feedbackId":32, "sender":"12345", "comment":"Test Comment", "replies":[ { "feedbackLogId":32, "feedbackReplyLogId":1, "comments":"So this is 1", "createdBy":"Jack", }, { "feedbackLogId":32, "feedbackReplyLogId":2, "comments":"2nd one", "createdBy":"Min", } ], } ] let repliesToRender = data.map((item) => item.replies) let numReplies = repliesToRender[0].length console.log(numReplies)
You can calculate reply per feedback using Array.prototype.map
for calculting total number of replies you can use Array.prototype.reduce
let data = [{"feedbackId":32,"sender":"12345","comment":"Test Comment","replies":[{"feedbackLogId":32,"feedbackReplyLogId":1,"comments":"So this is 1","createdBy":"Jack"},{"feedbackLogId":32,"feedbackReplyLogId":2,"comments":"2nd one","createdBy":"Min"}]},{"feedbackId":32,"sender":"12345","comment":"Test Comment","replies":[{"feedbackLogId":32,"feedbackReplyLogId":1,"comments":"So this is 1","createdBy":"Jack"},{"feedbackLogId":32,"feedbackReplyLogId":2,"comments":"2nd one","createdBy":"Min"}]}] let repliesCount = data.map(({replies}) => replies.length); console.log('per replies',repliesCount); let totalCount = data.reduce((a,c) => a + c.replies.length, 0); console.log('total replies ',totalCount)
Another approach. This will run faster in case of large data-sets, as it's not using loops.
let data = [
{
"feedbackId":32,
"sender":"12345",
"comment":"Test Comment",
"replies":[
{
"feedbackLogId":32,
"feedbackReplyLogId":1,
"comments":"So this is 1",
"createdBy":"Jack",
},
{
"feedbackLogId":32,
"feedbackReplyLogId":2,
"comments":"2nd one",
"createdBy":"Min",
}
],
}
]
let {replies} = data[0];
console.log(replies.length);
If replies count is needed for each of the objects, then below will return array of replies count for respective objects in order,
let eachObjectsRepliesCount = data.map(({replies}) => replies.length);
If replies count is needed for all the objects combined, then below will return the total replies count,
let repliesToRender = data.map((item) => item.replies)
let totalRepliesCount = repliesToRender[0].length
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