Swapping out a unique item found in two different arrays

Question

Swapping out a unique item found in two different arrays

Having 2 arrays:

var alleditvals= {username: "twooooo", password: "two_p", address: "two_add"};
var a= {username: "two", password: "two_p", address: "two_add"};

My goal is to replace only the difference ("twoooo") into the object a, making it similar to alleditvals.

In my code, a comes from an array named add_data, hence I utilize the map function:

add_data.map((a,i)=>
  i===count_edit ? alleditvals : a
)

where count_edit gets updated as a number. By checking if the index of add_data corresponds to count_edit, I include the value of alleditvals, otherwise retain the value in add_data (which is a). The challenge with this approach is that it replaces every object inside add_data when the condition holds true, including fields like password and address. Could you please suggest a method where I can selectively replace only the item that has changed?

Appreciate your help.

javascript arrays object

Answer 1

Answer №1

It seems like your intention is not to have variable a equal alleditvals entirely. As Kraylog pointed out, this would result in losing any properties unique to a that are not in alleditvals.

A better approach would be to iterate through the properties of the object and only copy over the fields that meet certain conditions. For example:

for (x in alleditvals) {
    if (x === “username”) {
        a[x] = alleditvals[x];
    }
    // add more conditions as needed
}

If you truly want to overwrite the differences and keep the properties of a that are not present in alleditvals, you can try something like this:

for (x in alleditvals) {
    if (
        a.hasOwnProperty(x) // only update if a already has the key from alleditvals
        && a[x] !== alleditvals[x]
        ) {
        a[x] = alleditvals[x];
    }
}

Answer 2

It seems like your intention is not to have variable a equal alleditvals entirely. As Kraylog pointed out, this would result in losing any properties unique to a that are not in alleditvals.

A better approach would be to iterate through the properties of the object and only copy over the fields that meet certain conditions. For example:

for (x in alleditvals) {
    if (x === “username”) {
        a[x] = alleditvals[x];
    }
    // add more conditions as needed
}

If you truly want to overwrite the differences and keep the properties of a that are not present in alleditvals, you can try something like this:

for (x in alleditvals) {
    if (
        a.hasOwnProperty(x) // only update if a already has the key from alleditvals
        && a[x] !== alleditvals[x]
        ) {
        a[x] = alleditvals[x];
    }
}

Answer 3

Answer №2

Implement the use of Object.assign.

var initialVals = {name: "John", age: 25, city: "New York"};
var changes = {age: 30, city: "Chicago"};

initialVals = Object.assign(initialVals, changes);

Answer 4

Implement the use of Object.assign.

var initialVals = {name: "John", age: 25, city: "New York"};
var changes = {age: 30, city: "Chicago"};

initialVals = Object.assign(initialVals, changes);

Answer 5

Answer №3

Understanding your query, the following solution may align with your requirements:

var alleditvals= {username: "twooooo", password: "two_p", address: "two_add"};

var a= {username: "two", password: "two_p", address: "two_add"};
var b= {username: "three", password: "two_p", address: "two_add"};
var c= {username: "four", password: "two_p", address: "two_add"};

let add_data=[a,b,c];

for (let x in add_data) {
   if(add_data[x].username!==alleditvals.username){
     add_data[x].username=alleditvals.username
   }
   /* other fields is same:
   if(add_data[x].password!==alleditvals.password){
     add_data[x].password=alleditvals.password
   }
   */
}

console.log(add_data)

Feel free to modify and execute this code snippet on this link.

Answer 6

Understanding your query, the following solution may align with your requirements:

var alleditvals= {username: "twooooo", password: "two_p", address: "two_add"};

var a= {username: "two", password: "two_p", address: "two_add"};
var b= {username: "three", password: "two_p", address: "two_add"};
var c= {username: "four", password: "two_p", address: "two_add"};

let add_data=[a,b,c];

for (let x in add_data) {
   if(add_data[x].username!==alleditvals.username){
     add_data[x].username=alleditvals.username
   }
   /* other fields is same:
   if(add_data[x].password!==alleditvals.password){
     add_data[x].password=alleditvals.password
   }
   */
}

console.log(add_data)

Feel free to modify and execute this code snippet on this link.

Answer 7

Answer №4

To effortlessly achieve this using modern javascript, simply utilize the spread operator:

newObject = { ...originalObject, ...newValues }

After this operation, newObject will contain all the properties of the original object along with any new ones from newValues that were not present in the original object.

If your goal is to combine both the new values from newValues and replace any existing properties in the original object with the corresponding ones from newValues, essentially merging over the original object, then you can simply reverse the order:

newObject = { ...originalObject, ...newValues }

Answer 8

To effortlessly achieve this using modern javascript, simply utilize the spread operator:

newObject = { ...originalObject, ...newValues }

After this operation, newObject will contain all the properties of the original object along with any new ones from newValues that were not present in the original object.

If your goal is to combine both the new values from newValues and replace any existing properties in the original object with the corresponding ones from newValues, essentially merging over the original object, then you can simply reverse the order:

newObject = { ...originalObject, ...newValues }

Swapping out a unique item found in two different arrays

Answer №1

Answer №2

Answer №3

Answer №4

Similar questions

Is it preferred to utilize v-show in combination with v-for?

A custom Mongoose schema attribute configured with distinct values

The leaflet popup fails to open for the second time

Switching the navbar image with HTML and JavaScript when clicked

In Django, the Ajax function will fail to execute if any of the required input fields are left empty

Discovering if a Powershell array includes some elements of another array

Tips for duplicating a 2D array in Python

Ways to incorporate react suspense with redux toolkit

The issue with the jQuery function lies in its inability to properly retrieve and return values

Having trouble initialising an array of objects in TypeScript? (TS1109: Expression expected)

Discover the ins and outs of the "DOM" within a string, treating it as HTML in AngularJS

Unable to trigger onActivated in Quasar (Vue 3) component

Is it possible to apply CSS based on a component's displayName?

Issues with Markdown text editor code, table, and list functionalities are causing malfunction

Guide to Implementing the GitHub Fetch API Polyfill

Numerous buttons activating a single modal component

Whenever I click on a button, I want to modify the background color of my react-modal

Discover identical JSON elements in 2 JSON arrays using JavaScript and add CSS styles to the corresponding items within a UL list

AngularJS integration with Google OAuth

Want to display a button depending on the page you are navigating from in Ionic?