javascript get array element by value code example

Example 1: find element in array javascript

const simpleArray = [3, 5, 7, 15];
const objectArray = [{ name: 'John' }, { name: 'Emma' }]

console.log( simpleArray.find(e => e === 7) )
// expected output 7

console.log( simpleArray.find(e => e === 10) )
// expected output undefined

console.log( objectArray.find(e => e.name === 'John') )
// expected output { name: 'John' }

Example 2: js array find

var ages = [3, 10, 18, 20];

function checkAdult(age) {
  return age >= 18;
}
/* find() runs the input function agenst all array components
   till the function returns a value
*/
ages.find(checkAdult);

Example 3: javascript get array value

var array = []
array[0] = "hi"
array[1] = "dude"
var done = false
while (done == false){
var valueToFind = "hi";
  var rounds = array.length;
  if (rounds < 0){
  return false
  }
  if (array[rounds] == valueToFind){
  done = true
    return rounds
  }
  rounds = rounds - 1
}