SheCodes JavaScript Cheatsheet

SheCodes JavaScript cheatsheet

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This website was built using technologies taught in SheCodes Coding Workshops including HTML, CSS, JavaScript, React, GitHub, Bootstrap and APIs. SheCodes teaches coding skills to busy women 👩‍💻

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Snippets categories:All General Variables Alerts & Prompts If else Strings Arrays Dates Numbers Objects Functions Debugging Selectors Events AJAX Element manipulation APIs

Variables

Variable creation

let school = "SheCodes";
let fullPackage = "SheCodes Pro";
let projects = 4;
let awesome = true;

Structure structure types

let students = ["Kate", "Julie", "Mariana"]; // Array

let kate = {
  firstName: "Kate",
  lastName: "Johnson",
  age: 23,
  canCode: true,
}; // Object

Alerts & Prompts

If else

if statement

let country = prompt("What country are you from?");

if (country === "Portugal") {
  alert("You are cool");
}

if (country !== "Portugal") {
  alert("Too bad for you");
}

Logical And

if (continent === "Europe" && language === "Portuguese") {
  alert("You are from Portugal 🇵🇹");
} else {
  alert("You are not from Portugal");
}

Strings

String concatenation

let firstName = "Julie";
let lastName = "Johnson";
let fullName = firstName + " " + lastName; // "Julie Johnson"

//or
let fullName = `${firstName} ${lastName}`;

Arrays

Dates

Get date data

let now = new Date();
now.getMinutes(); // 0,1,2, 12
now.getHours(); //1, 2, 3, 4
now.getDate(); //1, 2, 3, 4
now.getDay(); // 0, 1, 2
now.getMonth(); // 0, 1, 2
now.getFullYear(); // 2021

Numbers

Objects

Creating a new object

let fruit = new Object(); // "object constructor" syntax

let user = {}; // "object literal" syntax

let student = {
  firsName: "Julie",
  lastName: "Johnson",
};

let anotherStudent = {
  firstName: "Kate",
  lastName: "Robinson",
  female: true,
  greet: function () {
    alert("Hey");
  },
};

Reading an object properties

let user = {
  firstName: "Lady",
  lastName: "Gaga",
  gender: "female",
};

alert(user.firstName); // Lady
alert(user.lastName); // Gaga

// or
alert(user["firstName"]); // Lady
alert(user["lastName"]); // Gaga

Object Arrays

let users = [
  {
    firstName: "Bradley",
    lastName: "Cooper",
  },
  {
    firstName: "Lady",
    lastName: "Gaga",
  },
];

users.forEach(function (user, index) {
  for (let prop in user) {
    alert(prop + " is " + user[prop]);
  }
});

Enumerating the properties of an object

let user = {
  firstName: 'Lady',
  lastName: 'Gaga',
  gender: 'female'
}


for(let prop in user) {
  alert(prop); // firstName, lastName, gender
  alert(user[prop]); // 'Lady', 'Gaga', 'female'
}

Functions

JS Functions

function sayFact() {
  let name = prompt("What's your name?");

  if (name === "Sofia") {
    alert("Your name comes from the Greek -> Sophia");
  }
}

sayFact();

JS Functions Parameters

function fullName(firstName, lastName) {
  alert(firstName + " " + lastName);
}

let firstName = prompt("What's your first name?");
let lastName = prompt("What's your last name?");
fullName(firstName, lastName);
fullName("Kate", "Robinson");

JS Functions Return

function add(x, y) {
  return x + y;
}

let result = add(3, 4);
let result2 = add(result, 0);


function getFullName(firstName, lastName) {
  let fullName = firstName + " " + lastName;
  return fullName;
}

let userFullName = getFullName("Kate", "Robinson");
alert(userFullName); // Kate Robinson
alert(getFullName("Julie", "Smith")); // Julie Smith

Selectors

QuerySelector

let li = document.querySelector("li");
let day = document.querySelector(".day");
let paragraph = document.querySelector("ul#list p");

QuerySelectorAll

let lis = document.querySelectorAll("li");
let paragraphs = document.querySelectorAll("li#special p");

Events

Creating an event listener

function sayHi() {
  alert("hi");
}

let element = document.querySelector("#city");
element.addEventListener("click", sayHi);

AJAX

AJAX with Fetch

let root = 'https://jsonplaceholder.typicode.com'
let path = 'users/1'

fetch(root + '/' + path)
  .then(response => (
    response.json()
  ))
  .then(json => (
    console.log(json)
  ));

AJAX with Axios

<!DOCTYPE html>
<html>
  <head>
    <script src="https://unpkg.com/axios/dist/axios.min.js"></script>
  </head>
  <body>
    <script>
      function showUser(response) {
        alert(`The user name is ${response.data.name}`);
      }

      let url = "https://jsonplaceholder.typicode.com/users/1";
      axios.get(url).then(showUser);
    </script>
  </body>
</html>

Element manipulation

Forms

<form>
  <input type="text" id="email" />
</form>
<script>

function signUp(event) {
  event.preventDefault();
  let input = document.querySelector("#email");
  console.log(input.value);
}
let form = document.querySelector("form");
form.addEventListener("submit", signUp);
</script>

HTML Attributes Manipulation

let button = document.querySelector("input#button");
button.setAttribute("disabled", "disabled");

let email = document.querySelector("input#email");
email.removeAttribute("required");

CSS Styles

let boxElement = document.querySelector("#box");
boxElement.style.backgound = "red";
boxElement.style.padding = "10px 20px";
boxElement.style.marginRight = "10px";

APIs

Geolocation API

function handlePosition(position) {
  console.log(position.coords.latitude);
  console.log(position.coords.longitude);
}

navigator.geolocation.getCurrentPosition(handlePosition)

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