Javascript Functions Development Tutorials, Guides & Insights

• Bracket notation:

    console.log(person["age"]); // 25

Operators are used to perform operations on variables and values.

let x = 5;
let y = 3;

console.log(x + y); // Addition
console.log(x - y); // Subtraction
console.log(x * y); // Multiplication
console.log(x / y); // Division
console.log(x % y); // Modulus (remainder)

The apply method is similar to call, but it takes an array of arguments instead of passing them individually.

functionName.apply(thisArg, [arg1, arg2, ...]);

<table>
  <tr>
    <th>Function</th>


 <th>Description</th>
    <th>Example</th>
  </tr>
  <tr>
    <td><code>format(date, formatString)
    Formats the date according to the provided format string.
    format(new Date(), 'MMMM do, yyyy') => 'September 20th, 2024'
  
  
    addDays(date, amount)
    Returns a new date with the specified number of days added.
    addDays(new Date(), 10) => Date object 10 days in the future
  
  
    differenceInDays(dateLeft, dateRight)
    Returns the number of days between two dates.
    differenceInDays(new Date('2024-09-20'), new Date('2024-09-10')) => 10
  
  
    isBefore(date, dateToCompare)
    Checks if the first date is before the second one.
    isBefore(new Date('2024-09-10'), new Date('2024-09-20')) => true
  
  
    parse(dateString, formatString, referenceDate)
    Parses a date string according to the provided format string.
    parse('20th September 2024', 'do MMMM yyyy', new Date()) => Date object for 20th September 2024
  

This cheatsheet covers some of the most popular JavaScript utility libraries, providing a quick reference to key functions and their usage. These libraries help streamline your development process, reduce code duplication, and enhance the functionality of your JavaScript applications.