### Loops in JavaScript
Here’s a comprehensive guide to loops in JavaScript with examples:
### **1. For Loop**
The for loop is ideal when you know the exact number of iterations you need to perform.
#### **Syntax:**
for (initialization; condition; increment/decrement) { // Code to execute }
#### **Example:**
for (let i = 1; i <= 5; i++) { console.log(`Iteration: ${i}`); }
***Explanation:*
### **2. While Loop**
The while loop is used when the number of iterations is not predetermined and depends on a condition.
#### **Syntax:**
while (condition) { // Code to execute }
#### **Example:**
let count = 0; while (count < 5) { console.log(`Count is: ${count}`); count++; }
***Explanation:*
### **3. Do-While Loop**
The do-while loop ensures that the block of code is executed at least once, even if the condition is false.
#### **Syntax:**
do { // Code to execute } while (condition);
#### **Example:**
let number = 0; do { console.log(`Number is: ${number}`); number++; } while (number < 3);
***Explanation:*
### **4. For-In Loop**
The for-in loop is used to iterate over the properties of an object.
#### **Syntax:**
for (key in object) { // Code to execute }
#### **Example:**
const person = { name: "John", age: 30, city: "New York" }; for (let key in person) { console.log(`${key}: ${person[key]}`); }
***Output:*
name: John age: 30 city: New York
***Explanation:*
### **5. For-Of Loop**
The for-of loop is used to iterate over iterable objects like arrays, strings, maps, or sets.
#### **Syntax:**
for (variable of iterable) { // Code to execute }
#### **Example:**
const fruits = ["Apple", "Banana", "Cherry"]; for (let fruit of fruits) { console.log(fruit); }
***Output:*
Apple Banana Cherry
***Explanation:*
### **6. Breaking Out of Loops**
Use the break statement to exit a loop prematurely.
#### **Example:**
for (let i = 0; i < 10; i++) { if (i === 5) break; console.log(i); }
***Output:*
for (initialization; condition; increment/decrement) { // Code to execute }
### **7. Skipping Iterations**
Use the continue statement to skip the current iteration.
#### **Example:**
for (let i = 1; i <= 5; i++) { console.log(`Iteration: ${i}`); }
***Output:*
while (condition) { // Code to execute }
### **8. Nested Loops**
Loops can be nested inside one another for multidimensional iterations.
let count = 0; while (count < 5) { console.log(`Count is: ${count}`); count++; }
***Output:*
do { // Code to execute } while (condition);
### **9. Infinite Loops**
Be cautious of loops with conditions that never evaluate to false.
#### **Example:**
let number = 0; do { console.log(`Number is: ${number}`); number++; } while (number < 3);
Note: Avoid such loops unless there’s a break mechanism.
### **10. Looping Over Arrays**
Both for and for-of loops are commonly used with arrays.
#### **Example:**
for (key in object) { // Code to execute }
### **11. Looping Over Strings**
The for-of loop is also helpful for iterating through characters of a string.
const person = { name: "John", age: 30, city: "New York" }; for (let key in person) { console.log(`${key}: ${person[key]}`); }
By understanding and applying these loop types effectively, you can handle repetitive tasks and data structures in JavaScript efficiently. Let me know if you need clarification on any specific type!
Hi, I'm Abhay Singh Kathayat!
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