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Md. Injamul Alam
Md. Injamul Alam

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Loop Types in JavaScript

In this blog I'll go through different ways of looping in JavaScript with examples:

  • while
  • forEach
  • map
  • do while
  • for in
  • for of
  • for

while Loop

const developers = ['Injamul', 'Saurav', 'Tarek', 'Saiful'];

let developer = 0;

while (developer < developers.length) {
    console.log(developers[developer]);
    developer++;
}

/* Output: 
Injamul
Saurav
Tarek
Saiful
*/  
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forEach Loop

const developers = ['Injamul', 'Saurav', 'Tarek', 'Saiful'];

developers.forEach (developer =>{
    console.log(developer);
})

/* Output: 
Injamul
Saurav
Tarek
Saiful
*/  
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map Loop

const developers = ['Injamul', 'Saurav', 'Tarek', 'Saiful'];

developers.map (developer =>{
    console.log(developer);
    return developer;
})

/* Output: 
Injamul
Saurav
Tarek
Saiful
*/  
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do while Loop

const developers = ['Injamul', 'Saurav', 'Tarek', 'Saiful'];

let developer = 0
do {
    console.log(developers[developer]);
    developer++;
    }

while(developer < developers.length)

/* Output: 
Injamul
Saurav
Tarek
Saiful
*/  
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for of Loop

const developers = ['Injamul', 'Saurav', 'Tarek', 'Saiful'];

for (const developer of developers){
    console.log(developer);
    }

/* Output: 
Injamul
Saurav
Tarek
Saiful
*/  
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for in Loop

const developers = {
    1 : 'Injamul', 
    2 : 'Saurav', 
    3 : 'Tarek', 
    4 : 'Saiful'
};

for (const key in developers) {
    console.log(developers[key]);
}

/* Output: 
Injamul
Saurav
Tarek
Saiful
*/  
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for Loop

const developers = ['Injamul', 'Saurav', 'Tarek', 'Saiful'];

for (let developer = 0; developer < developers.length; developer++){
    console.log(developers[developer]);
    }

/* Output: 
Injamul
Saurav
Tarek
Saiful
*/  
Enter fullscreen mode Exit fullscreen mode

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