Question 408243 in Javascript Question posted in
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filter of Filter in javascript array

I have an array that I’m trying to filter:

const elements = ['apple'];

const objects = [
  { id: 1, fruit:[{"name": "apple" },{"name": "banana" }]},
  { id: 2, fruit:[{"name": "apple" },{"name": "orange" }]},
  { id: 3, fruit:[{"name": "orange" },{"name": "banana" }]},
  { id: 4, fruit:[{"name": "orange" },{"name": "banana" }]}
];

const results = objects.filter(obj => obj.fruit.filter( ele => elements.includes(ele.name)));
console.log(results);

I am getting the output as below but this not what I am expecting:

{id: 1, fruit:[{"name": "apple" },{"name": "banana" }]
{id: 2, fruit:[{"name": "apple" },{"name": "banana" }]

I want the output as below:

{ id: 1, fruit:[{"name": "apple" }]}
{ id: 2, fruit:[{"name": "apple" }]}
Tags:

2

Answers


  1. 0

    You could filter fruit and if it has elements take the outer object as result.

    const
    elements = ['apple'],
    objects = [{ id: 1, fruit: [{ name: "apple" }, { name: "banana" }] }, { id: 2, fruit: [{ name: "apple" }, { name: "orange" }] }, { id: 3, fruit: [{ name: "orange" }, { name: "banana" }] }, { id: 4, fruit: [{ name: "orange" }, { name: "banana" }] }],
    results = objects.reduce((r, o) => {
        const fruit = o.fruit.filter(({ name }) => elements.includes(name));
        if (fruit.length) r.push({ ...o, fruit });
        return r;
    }, []);
    
console.log(results);
    .as-console-wrapper { max-height: 100% !important; top: 0; }
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  2. 0

    Your snippet will work if you replace the inner filter with some:

    const elements = ['apple'];

const objects = [
  { id: 1, fruit:[{"name": "apple" },{"name": "banana" }]},
  { id: 2, fruit:[{"name": "apple" },{"name": "orange" }]},
  { id: 3, fruit:[{"name": "orange" },{"name": "banana" }]},
  { id: 4, fruit:[{"name": "orange" },{"name": "banana" }]}
];

const results = objects.filter(obj => obj.fruit.some( ele => elements.includes(ele.name)));
console.log(results);

    .filter() will always return a "truthy" result. Even an empty array ([]) will be seen as true. The .some() method on the other hand will only be true if the condition in the loop was met at least once.

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