Example 1 : Simple Callback function
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>JavaScript</title>
</head>
<body>
<script>
let x = function(){
console.log('I am called from inside a function');
}
let y = function(callback){
console.log('do something');
callback();
}
y(x);
</script>
</body>
</html>
Example 2 : Example of making functions abstract and calling it
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>JavaScript</title>
</head>
<body>
<script>
let add = function(num1,num2){
return num1+num2;
}
let multiply = function(num1,num2){
return num1*num2;
}
let calc = function(num1, num2, callback){
return callback(num1,num2);
}
console.log(calc(10,20,add));
</script>
</body>
</html>
Example 3 : Example of passing anonymous function to a function
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>JavaScript</title>
</head>
<body>
<script>
let calc = function(num1, num2, callback){
return callback(num1,num2);
}
console.log(calc(10,20,function(x,y) { return x+y; } ));
</script>
</body>
</html>
Example 4: Sorting of array
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>JavaScript</title>
</head>
<body>
<script>
var myArr = [{
num: 5,
str: 'apple'
}, {
num: 7,
str: 'cabbage'
}, {
num: 1,
str: 'lol'
}];
myArr.sort(function(x,y){
if(x.num > y.num){
return 1;
}else{
return -1;
}
});
console.log(myArr);
</script>
</body>
</html>
