In my front-end I am trying to map through nested objects which is coming from back-end Laravel collection:
[
{
"id": 1,
"name": "Chips",
"product_categories_id": 1,
"category": {
"id": 1,
"category": "Chips",
"brand": "Bombay Sweets"
}
},
{
"id": 2,
"name": "Book",
"product_categories_id": 2,
"category": {
"id": 2,
"category": "Shoe",
"brand": "Nike",
}
}]
I want to display the product name and related category name from nested object. My approach is:
products.map((product)=>{
console.log(product.name)
product.category.map((category)=>(
console.log(category.category)
))
})
which is not working at all. I spent huge amount of time to solve yet no luck.
the error it shows:
ProductListContainer.js:58 Uncaught TypeError: item.category.map is not a function
map method works only with Array. You can use product.category.category to access the value.
Finally solved by this:
products.map((product) => {
console.log(product.name)
Object.entries(product.category).map(() => (
console.log(product.category.category, product.category.brand)
))
})
Related
I'm trying to store in MongoDB one document with an object with the properties I want to map latter. My idea it's to create a function that will receive 2 params. First the object where I got to find the mapping, and second the object where I have to take the info from.
For example I want to store this JSON (that would be the first parameter in the function):
{
"name": "client.firstName",
"surname": "client.surname",
"age": "client.age",
"skills": [
{
"skillName": "client.skills[index].name",
"level": "client.skills[index].levelNumber",
"categories": [
{
"categoryName": "client.skills[index].categories[index].name",
"isImportant": "client.skills[index].categories[index].important"
}
]
}
]
}
And the second paramenter would be something like this (it's the object where you find the information.
{
"client": {
"firstName": "Jake",
"surname": "Long",
"age": 20,
"skills": [
{
"name": "Fly",
"level": 102,
"categories": [
{
"name": "air",
"important": true
},
{
"name": "superpower",
"important": false
}
]
},
{
"name": "FastSpeed",
"level": 163,
"categories": [
{
"name": "superpower",
"important": false
}
]
}
]
}
}
The idea it's: with de paths that I have in the first object, find it in the second one.. The problem I found it's when I have arrays, because when I defined the mapping rules I don't know how many positions will have the array I want to map. So in the mapping object (first) I'll only define the path but I'll not put it with the same lenght of the secondone because I don't know how much it will have.
I have a react page and one of my inputs is a file upload. When loading, I want to read in the file (it's JSON) and then show the file as a tree to allow my users to select nodes (rules) to run against another dataset. BUT, when I pick the JSON file and the 'onload' event handler actually fires off, the page just stops rendering, I get a blank screen. I'm not sure why, I can't see any errors, but I AM IGNORANT with react and kinda new with javascript as well. So, this is quite likely just a dumb thing I'm doing. Can someone point me at what I'm doing wrong here?
handleRules(event) {
const ruleRdr = new FileReader();
ruleRdr.onload = async (e) => {
const rBuf = (e.target.result);
const rData = JSON.parse(new TextDecoder().decode(rBuf));
// the data is there, but it's not mapping into the tree...!?!?!?
const tree = {
name: "QA/QC Rules",
id: 1,
toggled: true,
children: rData.map((wFlow, index) => ({
name: wFlow.WorkflowName,
id: index,
children: wFlow.Rules.map((rule, idx) => ({
name: rule.RuleName,
id: idx
}))
}))
};
this.setState({ ruleData: rData, hasRules: true, treeData: tree });
}
ruleRdr.readAsArrayBuffer(event.target.files[0]);
}
EDIT #1: I don't think it's the code above now, I think it might be my tree library (react-treebeard) or my ignorance on how I'm using it. The code produces what I think is useable data, but it isn't rendering it out.
{
"name": "QA/QC Rules",
"id": 1,
"toggled": true,
"children": [
{
"name": "COMP",
"id": 0,
"children": [
{
"name": "ParentMustHaveCat",
"id": 0
},
{
"name": "ParentMustHaveMfg",
"id": 1
},
{
"name": "ParentMustHaveFamily",
"id": 2
},
{
"name": "SymbolsMustHaveFamily",
"id": 3
}
]
},
{
"name": "PNLCOMP",
"id": 1,
"children": [
{
"name": "ParentMustHaveCat",
"id": 0
},
{
"name": "ParentMustHaveMfg",
"id": 1
},
{
"name": "ParentMustHaveFamily",
"id": 2
},
{
"name": "SymbolsMustHaveFamily",
"id": 3
}
]
},
{
"name": "PNLTERM",
"id": 2,
"children": [
{
"name": "ParentMustHaveCat",
"id": 0
},
{
"name": "ParentMustHaveMfg",
"id": 1
},
{
"name": "ParentMustHaveFamily",
"id": 2
},
{
"name": "SymbolsMustHaveFamily",
"id": 3
}
]
}
]
}
I figured it out. I switched to MUI since it has more components that I will want to use anyway. I got a similar issue with it as well and realized that I have duplicate IDs between the parent and the children, and was creating a kind of lock when trying to compare parent and child IDs in the MUI library. Totally on me - I'm dumb.
I am working with facebook JS SDK which returns user's information in JSON format. I know how to get the response like response.email which returns email address. But how to get an element from a nested array object? Example: user's education history may contain multiple arrays and each array will have an element such as "name" of "school". I want to get the element from the last array of an object.
This is a sample JSON I got:-
"education": [
{
"school": {
"id": "162285817180560",
"name": "Jhenaidah** School"
},
"type": "H**hool",
"year": {
"id": "14404**5610606",
"name": "2011"
},
"id": "855**14449421"
},
{
"concentration": [
{
"id": "15158**968",
"name": "Sof**ering"
},
{
"id": "20179020**7859",
"name": "Dig**ty"
}
],
"school": {
"id": "10827**27428",
"name": "Univer**g"
},
"type": "College",
"id": "9885**826013"
},
{
"concentration": [
{
"id": "108196**810",
"name": "Science"
}
],
"school": {
"id": "2772**996993",
"name": "some COLLEGE NAME I WANT TO GET"
},
"type": "College",
"year": {
"id": "1388*****",
"name": "2013"
},
"id": "8811215**16"
}]
Let's say I want to get "name": "some COLLEGE NAME I WANT TO GET" from the last array. How to do that with Javascript? I hope I could explain my problem. Thank you
Here is a JsFiddle Example
var json = '{}' // your data;
// convert to javascript object:
var obj = JSON.parse(json);
// get last item in array:
var last = obj.education[obj.education.length - 1].school.name;
// result: some COLLEGE NAME I WANT TO GET
If your json above was saved to an object called json, you could access the school name "some COLLEGE NAME I WANT TO GET" with the following:
json.education[2].school.name
If you know where that element is, then you can just select it as already mentioned by calling
var obj = FACEBOOK_ACTION;
obj.education[2].school.name
If you want to select specifically the last element, then use something like this:
obj.education[ obj.education.length - 1 ].scool.name
Try this,
if (myData.hasOwnProperty('merchant_id')) {
// do something here
}
where JSON myData is:
{
amount: "10.00",
email: "someone#example.com",
merchant_id: "123",
mobile_no: "9874563210",
order_id: "123456",
passkey: "1234"
}
This is a simple example for your understanding. In your scenario of nested objects, loop over your JSON data and use hasOwnProperty to check if key name exists.
I've done Dan Abramov's intro series on EggHead, and am working on a real world app. The domain is complex, so I'll run with a classic "blogs" example.
Let's say, we have an "index / list" page, where all we need to show are the blog post's title and blurb. So we have an API endpoint that returns that, and we store it in our state tree under blogs.byId.
Then, when you click through on a blog post, we actually need a bunch more info - e.g. the full blog post, and also tags and categories. Let's call this "blogs with metadata".
Stretching the example, there might be another completely separate page where I want to display a list of blog posts with the most recent 3 comments. Let's call this "blogs with comments".
My question is, how should my state tree treat these separate examples where I'm storing the same "thing" but in different "formats"? My initial hunch would be to treat them as completely separate data types, so my state tree would have eg: blogs.byId, blogsWithMetadata.byId and blogsWithComments.byId.
And then, even if every single blog post is cached in the blogs.byId section, the minute we need to view a blog post, the app completely ignores that warm blogs.byId cache, and looks only at blogsWithMetadata.byId - so we'd essentially be building up 3 separate caches of blog data, each with different amounts of info, and treating it as though they are as unrelated to each other as "blogs" and a completely unrelated table like "widgets" would be.
Is this correct? Or is there a better way?
The app currently rams them all under the same node, without distinction based on "format" and it's causing a world of pain.
There are probably many ways you could choose to do this. One of it is to use normalizr to structure your data.
Your blog post could have a data structure returned by the API like this:
{
"id": "123",
"author": {
"id": "1",
"name": "Paul"
},
"title": "My awesome blog post",
"comments": [{
"id": "324",
"commenter": {
"id": "2",
"name": "Nicole"
}
}],
"tags": [{
"id": "1",
"value": "awesome"
}, {
"id": "2",
"value": "journal"
}],
"categories": [{
"id": "1",
"value": "personal"
}, {
"id": "2",
"value": "life"
}]
}
which after normalizing, will look something like this:
{
entities: {
"post": {
"123": {
id: "123",
author: "1",
title: "My awesome blog post",
comments: ["324"],
tags: ["1", "2"],
categories: ["1", "2"],
}
},
"users": {
"1": { "id": "1", "name": "Paul" },
"2": { "id": "2", "name": "Nicole" }
},
"comments": {
"324": { id: "324", "commenter": "2" }
}
"tags": {
"1": { id: "1", "value": "awesome" },
"2": { id: "2", "value": "journal" },
}
"categories": {
"1": { id: "1", "value": "personal" },
"2": { id: "2", "value": "life" },
}
}
}
Subsequently, you could have a state for each page if you needed to:
{
entities: {...},
ui: {
blogs: {
posts: [1, 2],
hasComments: false,
// Displaying the blogs with or without comments
// could simply just be a boolean flag in state.
},
}
}
using reselect, you then create the selectors to pass the posts you want as props to the page Components.
I'm using ng-repeat directive to list a set of JSON data of the format
$scope.result=[
{
"id": 84,
"resource": {
"id": 3,
"name": "Resource Planning",
"description": "test"
},
"activity": {
"id": 6,
"name": "Activity Planning",
"description": "test"
}
}
]
My usage of ng-repeat is like this..
<div ng-repet="data in result">{{data.resource.name}} {{data.activity.name}}</div>
I'm able to display the name ie., "Resouce Planning" and "Activity Planning".
But I can't push the data if I'm doing like this
$scope.result.push({resource.name:result.resource.name,activity.name:result.activity.name})
from the controller.
Is there any way to push the name which is inside the object. And to display/list the same using ng-repeat?
Thanks
I don't really understand the question, but that's not how you build your javascript object. It should be something like:
$scope.result.push({
resource: {
name: result.resource.name
},
activity: {
name: result.activity.name
}
})