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Extract data from array if IDs match

I am struggling to find out a solution to my problem, but at the moment I cannot come up with the right one.
When I have my two arrays of objects I want to filter based on category IDs and extract the data from the second one into a new array for example :
const array1 = [
{id: 1, name: 'Tropical'},
{id: 2, name: 'Common'}
]
const array2 = [
{id:1, name: 'Banana', category_id: 1},
{id:2, name: 'Mango', category_id: 1},
{id:3, name: 'Apple', category_id: 2},
]
And when click happens I detect the first ID and render the new array only with data that matches the ID.
Click Tropical
New array :
[
{id:1, name: 'Banana', category_id: 1},
{id:2, name: 'Mango', category_id: 1},
]
I would be happy if someone give me a hint on how can I tackle this problem. Thanks !

Correct me if I am wrong, So you need a function that received a categoryId and you need to filter out array2 based on that category_id
You can try this
const array1 = [{
id: 1,
name: 'Tropical'
},
{
id: 2,
name: 'Common'
}
]
const array2 = [{
id: 1,
name: 'Banana',
category_id: 1
},
{
id: 2,
name: 'Mango',
category_id: 1
},
{
id: 3,
name: 'Apple',
category_id: 2
},
]
function categoryFruits(categoryId) {
return array2.filter(obj => obj.id === categoryId)
}
console.log(categoryFruits(3));

Use reduce to map over each item in array1 and filter to grab the items of that category_id
const array1 = [{
id: 1,
name: 'Tropical'
},
{
id: 2,
name: 'Common'
}
]
const array2 = [{
id: 1,
name: 'Banana',
category_id: 1
},
{
id: 2,
name: 'Mango',
category_id: 1
},
{
id: 3,
name: 'Apple',
category_id: 2
},
]
const obj = array1.reduce((acc, cur) => {
acc[cur.name] = array2.filter(v => v.category_id === cur.id)
return acc
}, {})
console.log(obj)

You could do something like filtering array2 and taking all the elements that have Tropical as name in array1.
const array1 = [
{id: 1, name: 'Tropical'},
{id: 2, name: 'Common'}
]
const array2 = [
{id:1, name: 'Banana', category_id: 1},
{id:2, name: 'Mango', category_id: 1},
{id:3, name: 'Apple', category_id: 2},
]
// take tropical friuts
let tropicalFriuts = array2.filter(x => x.category_id === array1.filter(y => y.name === 'Tropical')[0].id);
console.log(tropicalFriuts);

If I understood your problem you want before find the id, based on the name of the category, and later filter array2 data based on this id.
const array1 = [{
id: 1,
name: 'Tropical'
},
{
id: 2,
name: 'Common'
}
]
const array2 = [{
id: 1,
name: 'Banana',
category_id: 1
},
{
id: 2,
name: 'Mango',
category_id: 1
},
{
id: 3,
name: 'Apple',
category_id: 2
},
]
const id_key = array1.find(item=>item.name === 'Tropical').id;
const result = array2.filter(item=>item.category_id === id_key);
console.log(result);

JavaScript: add new property to array elements according to another array

I have two arrays.
When comparing, if arr1 property id matches with arr2 property id, then add new property tag: assign else add tag: ''
I have tried the below code:
var result = arr1.filter(({ id: id }) =>
!arr2.some(({ name: name }) => name === id)
);
Sample inputs:
var arr1 = [
{id:1, name: "ram"},
{id:24, name: "zen"},
{id: 3, name: "sam"}
]
var arr2 = [
{id:24, name: "zen"},
{id: 3, name: "sam"}
]
Expected Output:
[
{id:1, name: "ram", tag:''},
{id:24, name: "zen", tag: 'yes'},
{id: 3, name: "sam", tag: 'yes'}
]

Create a Set of ids in arr2 using Array#map
Again, using Array#map, iterate over arr1 and set tag using Set#has
const
arr1 = [ {id:1, name: "ram"}, {id:24, name: "zen"}, {id: 3, name: "sam"} ],
arr2 = [ {id:24, name: "zen"}, {id: 3, name: "sam"} ];
const arr2IdsSet = new Set( arr2.map(({ id }) => id) );
const res = arr1.map(e => ({ ...e, tag: arr2IdsSet.has(e.id) ? 'yes' : '' }));
console.log(res);

Get specific value from array object in a single line in typescript

I have a following array
const _array = [{id: 1, name: 'Adam'}, {id:3, name: 'Crystal'}, {id:2, name: 'Bob'}, {id: 4, name: 'Daisy'}];
How to write a single line of code in typescript to get item where name equal to Crystal from the array?

You can use array find method like following:
const _array = [
{ id: 1, name: "Adam" },
{ id: 3, name: "Crystal" },
{ id: 2, name: "Bob" },
{ id: 4, name: "Daisy" },
];
const item = _array.find((item) => item.name === "Crystal");
console.log(item);
Output
{ id: 3, name: 'Crystal' }

Search/Filter nested Array Javascript/Lodash

For my React.js project I would like to create a search-filter of a nested Array. Users will search with an input-field.
var dataExample = [
{
type: "human", details: [
{id: 1, name: "Peter", description: "friendly, black-hair"},
{id: 5, name: "Susan", description: "blond"}
]
},
{
type: "animal", details: [
{id: 2, name: "Will", description: "lazy, cute"},
{id: 3, name: "Bonny", description: "beautiful"}
]
}
];
In my search-input-field I want to look for "name" or something in "description". The data structure of the array should remain the same.
The output when I'm searching for "friendly" or "Peter" should be:
[
{
type: "human", details: [
{id: 1, name: "Peter", description: "friendly, black-hair"}
]
}
];
Now I tried something like this:
let myfilter = dataExample.filter((data) => {
data.details.filter((items) => {
return (items.type.indexOf("human") !== -1 || //input of user
items.description.indexOf("friendly"))
})
})
Unfortunately, this is not how it works. Can anybody help me? Lodash would be no problem, too. Thank you so much.

You can use array#reduce with array#filter and to check for your word you can use string#incldues.
const dataExample = [ { type: "human", details: [ {id: 1, name: "Peter", description: "friendly, black-hair"}, {id: 5, name: "Susan", description: "blond"} ] }, { type: "animal",details: [ {id: 2, name: "Will", description: "lazy, cute"}, {id: 3, name: "Bonny", description: "beautiful"} ] } ],
term = 'Peter',
result = dataExample.reduce((r, {type,details}) => {
let o = details.filter(({name,description}) => name.includes(term) || description.includes(term));
if(o && o.length)
r.push({type, details : [...o]});
return r;
},[]);
console.log(result);

Here are some examples without lodash.
var dataAll = [
{
type: "human",
details: [
{id: 1, name: "Peter", description: "friendly, black-hair"},
{id: 5, name: "Susan", description: "blond"}
]
},
{
type: "animal",
details: [
{id: 2, name: "Will", description: "lazy, cute"},
{id: 3, name: "Bonny", description: "beautiful"}
]
}
];
var entryTypeFilter = data => data.type.indexOf("hum") !== -1;
var entryDetailDescFilter = data => data.description.indexOf("friend") !== -1;
var entryDetailsMapper = data => {
return {
type: data.type,
details: data.details.filter(entryDetailDescFilter)
};
};
var entryNoDetailsFilter = data => data.details && data.details.length !== 0;
var dataFilteredByType = dataAll.filter(entryTypeFilter);
var dataFilteredByDesc = dataAll.map(entryDetailsMapper);
var dataFilteredByTypeAndDesc = dataAll.filter(entryTypeFilter).map(entryDetailsMapper);
var dataFilteredByDescTrimmingEmptyDetailEntries = dataAll.map(entryDetailsMapper).filter(entryNoDetailsFilter);
In modern javascript you might want to search on how to use the ... keyword for the mapping callback functions.

Categorize Similar items into separate objects from Array lists

I have an array of items that I get from API as a response body.
data = [{id: 1, category: "kitchen", name: "noodles"},
{id: 2, category: "general", name: "Wi-Fi"},
{id: 3, category: "sports", name: "Football"},]
I want to iterate over the arrays, and get the data like :
var categorized = {
kitchen: [{id: 1, category: "kitchen", name: "noodles"}],
general : [{id: 2, category: "general", name: "Wi-Fi"}],
sports : [{id: 3, category: "sports", name: "Football"}]
};
Is there any lodash methods, or any ES6 shortcuts for this ?

In answer to your question 'is there a lodash method?' Yes: https://lodash.com/docs/4.17.4#groupBy. For your specific example:
const categorized = _.groupBy(data, 'category');
Edit: You could roll your own groupBy type function with ES6 as in another example. But if you are using lodash anyway this is a whole lot cleaner.

I used array.reduce to get the structure
var data = [{
id: 1,
category: "kitchen",
name: "noodles"
}, {
id: 2,
category: "general",
name: "Wi-Fi"
}, {
id: 3,
category: "sports",
name: "Football"
}]
var newData = data.reduce(function(obj, v, i) {
obj[v.category] = obj[v.category] || [];
obj[v.category].push(v);
return obj;
}, {});
console.log(newData);
In ES6 you could so using:
var newData = data.reduce((obj, v, i)=> {
obj[v.category] = obj[v.category] || [];
obj[v.category].push(v);
return obj;
}, {});
console.log(newData);