Mastering Conditional Statements in JavaScript: if, else, and switch Explained

### Conditional Statements in JavaScript (if, else, switch)

Conditional statements in JavaScript are used to perform different actions based on different conditions. They help control the flow of execution in a program and allow the program to make decisions. The most commonly used conditional statements are if, else, and switch.

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### 1. **if Statement**

The if statement is used to execute a block of code if a specified condition is true.

#### Syntax:

if (condition) {
  // code to be executed if condition is true
}

#### Example:

let age = 18;
if (age >= 18) {
  console.log("You are an adult.");
}

Output: You are an adult.

---

### 2. **if...else Statement**

The if...else statement allows you to execute one block of code if the condition is true, and another block of code if the condition is false.

#### Syntax:

if (condition) {
  // code to be executed if condition is true
} else {
  // code to be executed if condition is false
}

#### Example:

let age = 16;
if (age >= 18) {
  console.log("You are an adult.");
} else {
  console.log("You are a minor.");
}

Output: You are a minor.

---

### 3. **if...else if...else Statement**

The if...else if...else statement is used when you need to check multiple conditions. If the first condition is false, it checks the next condition and so on.

#### Syntax:

if (condition1) {
  // code to be executed if condition1 is true
} else if (condition2) {
  // code to be executed if condition2 is true
} else {
  // code to be executed if no conditions are true
}

#### Example:

let age = 20;
if (age < 18) {
  console.log("You are a minor.");
} else if (age >= 18 && age <= 65) {
  console.log("You are an adult.");
} else {
  console.log("You are a senior.");
}

Output: You are an adult.

---

### 4. **switch Statement**

The switch statement is used to perform different actions based on different conditions. It is a cleaner and more readable alternative to using many if...else if statements.

Syntax:

switch (expression) {
  case value1:
    // code to be executed if expression === value1
    break;
  case value2:
    // code to be executed if expression === value2
    break;
  // More cases can be added
  default:
    // code to be executed if no case matches
}

#### Example:

let fruit = "apple";
switch (fruit) {
  case "apple":
    console.log("You selected an apple.");
    break;
  case "banana":
    console.log("You selected a banana.");
    break;
  case "orange":
    console.log("You selected an orange.");
    break;
  default:
    console.log("Unknown fruit.");
}

Output: You selected an apple.

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### 5. **Comparison with if...else vs switch**

• if...else is more flexible and allows for complex conditions (e.g., using logical operators).
• switch is more efficient and easier to read when checking a variable for several possible values.

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### Conclusion

Conditional statements in JavaScript (if, else, and switch) are essential for controlling the flow of execution based on different conditions. Use if for basic checks, if...else for binary choices, and switch when dealing with multiple possible conditions. Understanding these structures will improve your ability to write clean and efficient code.

Hi, I'm Abhay Singh Kathayat!
I am a full-stack developer with expertise in both front-end and back-end technologies. I work with a variety of programming languages and frameworks to build efficient, scalable, and user-friendly applications.
Feel free to reach out to me at my business email: kaashshorts28@gmail.com.

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