forEach java script code example

Example 1: javascript foreach

const avengers = ['thor', 'captain america', 'hulk'];
avengers.forEach((item, index)=>{
	console.log(index, item)
})

Example 2: javascript foreach

var colors = ['red', 'blue', 'green'];

colors.forEach(function(color) {
  console.log(color);
});

Example 3: foreach javascript

let words = ['one', 'two', 'three', 'four'];
words.forEach((word) => {
  console.log(word);
});
// one
// two
// three
// four

Example 4: javascript foreach example

var colors = ["red", "blue", "green"];
colors.forEach(function(color) {
    console.log(color);
});

Example 5: javascript .foreach

let colors = ['red', 'blue', 'green'];
// idx and sourceArr optional; sourceArr == colors
colors.forEach(function(color, idx, sourceArr) {
	console.log(color, idx, sourceArr)
});
// Output:
// red 0 ['red', 'blue', 'green']
// blue 1 ['red', 'blue', 'green']
// green 2 ['red', 'blue', 'green']

Example 6: forEach

const arraySparse = [1,3,,7]
let numCallbackRuns = 0

arraySparse.forEach((element) => {
  console.log(element)
  numCallbackRuns++
})

console.log("numCallbackRuns: ", numCallbackRuns)

// 1
// 3
// 7
// numCallbackRuns: 3
// comment: as you can see the missing value between 3 and 7 didn't invoke callback function.