Below are the conditional statements present in Javascript.

1. If

If is used to execute a block of code based on a condition.

Syntax

if(condition){
    // code
}

Example

let age = 20; 

if (age > 18) {
  console.log('Adult');
}

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2. If-else

If is used to execute a block of code based on a condition. and else part is used to execute the block of code when the condition fails.

Syntax

if(condition){
    // code
} else {
    // code
}

Example

let age=7;

if(age<0) {
console.log('invalid age');
} else if (age<5 && age >0) {
console.log('Infant');
} else if (age>=5 && age<=18) {
  console.log('child');
} else if (age>18) {
  console.log("Adult");
}

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3. Switch

Switch is used to replace nested If-else statements.

Syntax

switch(condition){
    case 'value1' :
        //code
        [break;]
    case 'value2' :
        //code
        [break;]
    .......
    default :
        //code
        [break;]
}

Example

// what is hello in different languages
let language = "italian";

switch(language){
  case "french" :
    console.log('BONJOUR');
    break;
  
  case "spanish":
    console.log('Hola');
    break;
  
  case "italian" :
    console.log("Ciao");
    break;
  
  case "hindi" :
    console.log("Namaste");
    break;
  
  default:
    console.log('Hello');
}

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