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@Megajjks
Created October 18, 2020 21:52
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Ways to itered a data in javascript Interview questions
// 1. Demonstrate all the different ways to iterate the below array
const myArray = [1, 2, 3, 4, 5, 6];
// 1 method
for (let index = 0; index < myArray.length; index++) {
console.log(myArray[index])
}
// 2 method
myArray.forEach((element) => {console.log(myArray[element]);});
// 3 method, not is the best way but pass, but in practice it is only used in objects or arrays that are transformed or mutated
const newArray = myArray.map((idx)=>(console.log(idx)));
// 2. Demonstrate all the different ways to iterate the keys of
// the below object
const myObject = { x: 1, y: "hi" };
// 1 method
for (const key in myObject) {
console.log(key);
}
// 2 method
const keys = Object.keys(myObject);
console.log(keys)
// 3 method
for (const [key, value] of Object.entries(myObject)) {
console.log(key);
}
// 4 method
Object.entries(myObject).forEach(([key, value]) => {
console.log(key);
});
// 3. Repeat #2, demonstrate different ways to iterate
// the values of "myObject"
// 1 method
const obj = myObject.map((item) => console.log(`x:${item.x} y:${item.y}`));
// 2 method
for (const key in myObject) {
console.log(`${key}: ${myObject[key]}`);
}
// 3 method
Object.values(myObject).forEach((val) => console.log(val));
// 4 method
for (const [key, value] of Object.entries(myObject)) {
console.log(`${key}: ${value}`);
}
// 5 method
Object.entries(myObject).forEach(([key, value]) => {
console.log(`${key}: ${value}`);
});
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