React js(codecademy course)

React js codecademy course

💖React.js is a JavaScript library.

 💖It was developed by engineers at Facebook.

💖Here are just a few of the reasons why people choose to program with React:
                      1.React is fast.
                      2.React is modular.
                      3.React is scalable.
                      4.React is flexible.
                      5. React is popular.


What is JSX?

💖JSX is not valid JavaScript. Web browsers can't read it!

💖 It was written to be used with React. JSX code looks a lot like HTML.

JSX Elements

💖A basic unit of JSX is called a JSX element.

💖Here's an example of a JSX element:

<h1>Hello world</h1>

💖This JSX element looks exactly like HTML!



JSX elements and their surroundings

💖JSX elements are treated as JavaScript expressions. 

 💖They can go anywhere that JavaScript expressions can go.

💖That means that a JSX element can be saved in a variable, passed to a  function, stored in an object or array...you name it.

💖Here's an example of a JSX element being saved in a variable:

   const navBar = <nav>I am a nav bar</nav>;

Attributes in JSX 

💖A JSX attribute is written using HTML-like syntax: a name, followed by an equals sign, followed by a value.

💖The value should be wrapped in quotes, like this

       my-attribute-name="my-attribute-value"