Question

How to use array in JavaScript

Answer 1

const arr = ["JavaScript", "PHP", "C", "C++"];
     
console.log(arr[0]);
console.log(arr[1]);
console.log(arr[2]);


     
/*
run:
     
JavaScript
PHP
C 
     
*/
 

 

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Answer 2

<!-- HTML -->
<input type="text" id="test">

/* JavaScript */ 
const arr = ["JavaScript", "PHP", "C"];
    
document.getElementById("test").value = arr;

    
/*
run:
    
JavaScript,PHP,C
    
*/

 

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Answer 3

<!-- HTML -->
<input type="text" id="test">

/* JavaScript */ 
const arr = ["JavaScript", "PHP", "C"];
    
document.getElementById("test").value = arr[0];

    
/*
run:
    
JavaScript
    
*/

 

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Answer 4

const arr = ["JavaScript", "PHP", "C"];
let s = "";
        
for (i = 0; i < arr.length; i++) { 
     s += arr[i] + ", ";
}

console.log(s);

    
/*
run:
    
JavaScript, PHP, C,
    
*/

 

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Answer 5

let arr = [];
     
arr[0] = "C";
arr[1] = "C++";
arr[2] = "JavaScript";
     
for (let i = 0; i < arr.length; i++) { 
    console.log(arr[i]);
}   

     
/*
run:
     
C
C++
JavaScript
    
*/

 

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Answer 6

const arr = [9, 7, 2, 8];
 
console.log(arr);
 
console.log(arr.length);
 
 
/*
run:
 
[9, 7, 2, 8] 
4
 
*/

 

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Answer 7

let array = [1, 2, 3, 4];
console.log(array);

/*
fill(value)
fill(value, start)
fill(value, start, end)
*/

array = array.fill(0, 2, 4);
console.log(array);

 
 
/*
run:
 
[ 1, 2, 3, 4 ]
[ 1, 2, 0, 0 ]
 
*/

 

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