Exploring ways to compare and update values in an array of objects using JavaScript

Question

Exploring ways to compare and update values in an array of objects using JavaScript

I have a situation where I need to compare the names and values of two arrays filled with objects.

const array1 = [
  {
    name: 'Sarah',
    value: null
  },
  {
    name: 'Michael',
    value: null
  }
]

const array2 = [
  {
    name: 'Sarah',
    value: '1'
  }
]

If the object's name property in array2 is found in array1, then update the value of the name to '0', otherwise leave it unchanged.

The desired outcome should be :

[
  {
    "name": "Sarah",
    "value": "0"
  },
  {
    "name": "Michael",
    "value": null
]

Could someone please provide guidance on how to achieve this?

javascript arrays

Answer 1

Answer №1

If you are looking to update values in one array based on another, you can achieve this using two separate forEach() loops:

const firstArray = [
  {
    name: 'Alice',
    value: null
  },
  {
    name: 'Bob',
    value: null
  },
  {
    name: 'Charlie',
    value: null
  }
]

const secondArray = [
  {
    name: 'Alice',
    value: '1'
  },
  {
    name: 'Charlie',
    value: '2'
  }
]

secondArray.forEach((item) => {
  firstArray.forEach((element) => {
     if(element.name === item.name){
       element.value = item.value;
     }
  });
});
console.log(firstArray);

Answer 2

If you are looking to update values in one array based on another, you can achieve this using two separate forEach() loops:

const firstArray = [
  {
    name: 'Alice',
    value: null
  },
  {
    name: 'Bob',
    value: null
  },
  {
    name: 'Charlie',
    value: null
  }
]

const secondArray = [
  {
    name: 'Alice',
    value: '1'
  },
  {
    name: 'Charlie',
    value: '2'
  }
]

secondArray.forEach((item) => {
  firstArray.forEach((element) => {
     if(element.name === item.name){
       element.value = item.value;
     }
  });
});
console.log(firstArray);

Answer 3

Answer №2

Here is the straightforward solution:

Let's iterate through each item in array1 and compare it with each item in array2. If we find a match based on name, we will set the value of record1 to "0".

Answer 4

Here is the straightforward solution:

Let's iterate through each item in array1 and compare it with each item in array2. If we find a match based on name, we will set the value of record1 to "0".

Answer 5

Answer №3

You can implement a solution by applying the map function to the first array and then using the find method. Keep in mind that this approach ensures that the original content of array1 remains unchanged.

const array1 = [
  {
    name: 'Alice',
    value: null
  },
  {
    name: 'Bob',
    value: null
  }
];

const array2 = [
  {
    name: 'Alice',
    value: '1'
  }
];

const updatedArray = array1.map(item1 => {
  const newItem = { ...item1 };
  if (array2.find(item2 => item2.name === item1.name)) {
    newItem.value = 1;
  }
  return newItem;
});

console.log(updatedArray);

Answer 6

You can implement a solution by applying the map function to the first array and then using the find method. Keep in mind that this approach ensures that the original content of array1 remains unchanged.

const array1 = [
  {
    name: 'Alice',
    value: null
  },
  {
    name: 'Bob',
    value: null
  }
];

const array2 = [
  {
    name: 'Alice',
    value: '1'
  }
];

const updatedArray = array1.map(item1 => {
  const newItem = { ...item1 };
  if (array2.find(item2 => item2.name === item1.name)) {
    newItem.value = 1;
  }
  return newItem;
});

console.log(updatedArray);

Answer 7

Answer №4

It's quite straightforward:

Below is the code snippet you can utilize:

array2.forEach(
                function(parent){

                    array1.find(function(child)
                    {
                        if(child.name==parent.name){
                            child.value=0;

                        }
                    })

                    }

);

Answer 8

It's quite straightforward:

Below is the code snippet you can utilize:

array2.forEach(
                function(parent){

                    array1.find(function(child)
                    {
                        if(child.name==parent.name){
                            child.value=0;

                        }
                    })

                    }

);

Answer 9

Answer №5

Give this a shot:

const listOne = [
{
    name: 'Sarah',
    number: null
},
{
    name: 'Emily',
    number: null
},
{
    name: 'Brandon',
    number: null
}
]

const listTwo = [
{
    name: 'Sarah',
    number: '0'
},
{
    name: 'Brandon',
    number: '0'
}
]


var updatedList = listOne.map(item => {
    if(listTwo.some(function (entry) { return entry.name === item.name })){
        item.number = 0;
    }
    return item;
})

Answer 10

Give this a shot:

const listOne = [
{
    name: 'Sarah',
    number: null
},
{
    name: 'Emily',
    number: null
},
{
    name: 'Brandon',
    number: null
}
]

const listTwo = [
{
    name: 'Sarah',
    number: '0'
},
{
    name: 'Brandon',
    number: '0'
}
]


var updatedList = listOne.map(item => {
    if(listTwo.some(function (entry) { return entry.name === item.name })){
        item.number = 0;
    }
    return item;
})

Exploring ways to compare and update values in an array of objects using JavaScript

Answer №1

Answer №2

Answer №3

Answer №4

Answer №5

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