Question 52790 in Javascript Question posted in
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How to loop through json data to output some specific data structure? – Javascript

I am trying to loop through my JSON data and form an array of objects. I am counting the number of fruits in each State.
My JSON data is as below:

const data = 
[
  { 
    “State”: “California”, “Fruits”: [{"name": “oranges”, "code": “112”}, {"name": “apple, "code": “111”}] 
  },
 { 
    “State”: “Arizona”, “Fruits”: [{"name": “oranges”, "code": “112”}, {"name": “apple, "code": “111”}, {"name": “kiwi, "code": “999”}] 
  },
 { 
    “State”: “Ohio”, “Fruits”: [{"name": “oranges”, "code": “112”}, {"name": “kiwi, "code": “999”}] 
  },
 { 
    “State”: “Arizona”, “Fruits”: [{"name": “kiwi, "code": “999”}] 
  },
{ 
    “State”: “California”, “Fruits”: [{"name": “oranges”, "code": “112”}, {"name": “apple, "code": “111”}, {"name": “kiwi, "code": “999”}] 
  },
 { 
    “State”: “Arizona”, “Fruits”: [{"name": “oranges”, "code": “112”}, {"name": “apple, "code": “111”}] 
  },
]

My desired output is as below:

[
  {
    State: ‘California’,
    Fruits: [
      { name: 'Apples', count: 2 },
      { name: 'Oranges', count: 2 },
      { name: 'Kiwi', count: 1 }
    ]
  },
  {
    State: ‘Arizona’,
    Fruits: [
      { name: 'Apples', count: 2 },
      { name: 'Oranges', count: 2 },
      { name: 'Kiwi', count: 2 }
    ]
  },
  {
    State: ‘Ohio’,
    Fruits: [
      { name: 'Oranges', count: 1 },
      { name: 'Kiwi', count: 1 }
    ]
  }
];

When i loop through the JSON data and count the fruits i am unable to get it in the desired format. below is my code:

let obj = {}

for(let i=0; i<data.length; i++){
    for(let j=0; j<data[i].fruits.length; j++){

      obj[data[i].fruits[j].name]? obj[data[i].fruits[j].name]++ : obj[data[i].fruits[j].name]=1;


    }
}

The above loop gives the output as:

{
 "Apples" : 4,
 "Oranges": 5,
 "kiwi": 4
}

How do i change my loop to get my desired format??

Tags:

2

Answers


  1. 0

    You can first group all the fruits by state, then use Array#reduce to count in each state.

    const data=[{State:"California",Fruits:[{name:"oranges",code:"112"},{name:"apple",code:"111"}]},{State:"Arizona",Fruits:[{name:"oranges",code:"112"},{name:"apple",code:"111"},{name:"kiwi",code:"999"}]},{State:"Ohio",Fruits:[{name:"oranges",code:"112"},{name:"kiwi",code:"999"}]},{State:"Arizona",Fruits:[{name:"kiwi",code:"999"}]},{State:"California",Fruits:[{name:"oranges",code:"112"},{name:"apple",code:"111"},{name:"kiwi",code:"999"}]},{State:"Arizona",Fruits:[{name:"oranges",code:"112"},{name:"apple",code:"111"}]},];
let res = Object.entries(data.flatMap(x => x.Fruits.map(f => [x.State, f.name]))
  .reduce((acc, [State, fruit]) => {
    (acc[State] ??= []).push(fruit);
    return acc;
  }, {})).map(([State, fruits]) => ({State, fruits: Object.values(fruits.reduce((acc, name) => {
    (acc[name] ??= {name, count: 0}).count++;
    return acc;
  }, {}))}));
console.log(res);
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  2. 0

    You can try this:

    function Test() {
        const data = 
            [
            { 
                "State": "California", "Fruits": [{"name": "oranges", "code": "112"}, {"name": "apple", "code": "111"}] 
            },
            { 
                "State": "Arizona", "Fruits": [{"name": "oranges", "code": "112"}, {"name": "apple", "code": "111"}, {"name": "kiwi", "code": "999"}] 
            },
            { 
                "State": "Ohio", "Fruits": [{"name": "oranges", "code": "112"}, {"name": "kiwi", "code": "999"}] 
            },
            { 
                "State": "Arizona", "Fruits": [{"name": "kiwi", "code": "999"}] 
            },
            { 
                "State": "California", "Fruits": [{"name": "oranges", "code": "112"}, {"name": "apple", "code": "111"}, {"name": "kiwi", "code": "999"}] 
            },
            { 
                "State": "Arizona", "Fruits": [{"name": "oranges", "code": "112"}, {"name": "apple", "code": "111"}] 
            },
        ];

        data.forEach(x => {
            let temp = {};
            x.Fruits.forEach(y => {
                if(!Object.hasOwn(temp, y.name)){
                    temp[y.name] = 1;
                } else {
                    temp[y.name] += 1;
                }
            });

            let tempArr = [];
            for (let key in temp) {
                tempArr.push({
                    name: key,
                    count: temp[key]
                })
            }

            x.Fruits = tempArr;
        });

        console.log(data);
    }
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