In this tutorial, you will learn about JavaScript arrow function with the help of examples.
Arrow function is one of the features introduced in the ES6 version of JavaScript. It allows you to create functions in a cleaner way compared to regular functions. For example,
This function
// function expression
let x = function(x, y) {
return x * y;
}
can be written as
// using arrow functions
let x = (x, y) => x * y;
using an arrow function.
Arrow Function Syntax
The syntax of the arrow function is:
let myFunction = (arg1, arg2, ...argN) => {
statement(s)
}
Here,
myFunctionis the name of the functionarg1, arg2, ...argNare the function argumentsstatement(s)is the function body
If the body has single statement or expression, you can write arrow function as:
let myFunction = (arg1, arg2, ...argN) => expression
Example 1: Arrow Function with No Argument
If a function doesn’t take any argument, then you should use empty parentheses. For example,
let greet = () => console.log('Hello');
greet(); // Hello
Example 2: Arrow Function with One Argument
If a function has only one argument, you can omit the parentheses. For example,
let greet = x => console.log(x);
greet('Hello'); // Hello
Example 3: Arrow Function as an Expression
You can also dynamically create a function and use it as an expression. For example,
let age = 5;
let welcome = (age < 18) ?
() => console.log('Baby') :
() => console.log('Adult');
welcome(); // Baby
Example 4: Multiline Arrow Functions
If a function body has multiple statements, you need to put them inside curly brackets {}. For example,
let sum = (a, b) => {
let result = a + b;
return result;
}
let result1 = sum(5,7);
console.log(result1); // 12
this with Arrow Function
Inside a regular function, this keyword refers to the function where it is called.
However, this is not associated with arrow functions. Arrow function does not have its own this. So whenever you call this, it refers to its parent scope. For example,
Inside a regular function
function Person() {
this.name = 'Jack',
this.age = 25,
this.sayName = function () {
// this is accessible
console.log(this.age);
function innerFunc() {
// this refers to the global object
console.log(this.age);
console.log(this);
}
innerFunc();
}
}
let x = new Person();
x.sayName();
Output
25
undefined
Window {}
Hope this helps in improvising your JavaScript code for your Power Platform Implementations
Happy CRM’ing.
Cheers,
PMDY
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