loop a object in javascript code example

Example 1: javascript loop through object

Object.entries(obj).forEach(
    ([key, value]) => console.log(key, value)
);

Example 2: loop through object javascript

var p = {
    "p1": "value1",
    "p2": "value2",
    "p3": "value3"
};

// for-in
for (var key in p) {
    if (p.hasOwnProperty(key)) {
        console.log(key + " -> " + p[key]);
    }
}

// for-of with Object.keys()
for (var key of Object.keys(p)) {
    console.log(key + " -> " + p[key])
}

// Object.entries()
for (let [key, value] of Object.entries(p)) {
  console.log(`${key}: ${value}`);
}

Example 3: javascript loop through object

for (var property in object) {
  if (object.hasOwnProperty(property)) {
    // Do things here
  }
}

Example 4: javascript loop object

let obj = {
  key1: "value1",
  key2: "value2",
  key3: "value3"
}

Object.keys(obj).forEach(key => {
    console.log(key, obj[key]);
});
// key1 value1
// key2 value2
// key3 value3

// using for in - same output as above
for (let key in obj) {
  let value = obj[key];
  console.log(key, value);
}

Example 5: how to loop object javascript

var obj = {a: 1, b: 2, c: 3};

for (const prop in obj) {
  console.log(`obj.${prop} = ${obj[prop]}`);
}

// Salida:
// "obj.a = 1"
// "obj.b = 2"
// "obj.c = 3"

Example 6: javascript loop through object

Object.entries(obj).forEach(
    ([key, value]) => console.log(key, value)
);

// Loop using forEach
arr.forEach((item, index) => {
    // TODO
})

// Loop using for...of
for (const item of arr) {
    await something()
}

// Clone new array (not changing the old one)
const arr = [1,2,3]
const newArray = arr.map(item => item * 2)
console.log(newArray)

// Filter array by condition
const arr = [1,2,3,1]
const newArray = arr.filter(item => {
    if (item === 1) { return item }
})
console.log(newArray)

// Join array
const arr1 = [1,2,3]
const arr2 = [4,5,6]
const arr3 = [...arr1, ...arr2]
console.log(arr3)

// Get a property of object
const { email, address } = user
console.log(email, address)

// Copy object/array
const obj = { name: 'my name' }
const clone = { ...obj }
console.log(obj === clone)