React Router DOM v4 Tutorial (with Examples) • techiediaries

#React Router DOM v4 Tutorial (with Examples)  #reactjs #javascript #Programming #coding

  • The < Route > component is one of the most useful components of React Router v4 and the idea behind it is simple, wherever you want to render something when only there is a match with the location’s path you can use a Route component.
  • We can just append the name to be used for the variable plus a colon : to the end of the route’s path, for example: – – When there is a path match an object which has the following properties will be created and passed to the component: – -…
  • First we import the necessary routing components such as Route and BrowserRouter – – Next we create the base layout component, besides common HTML tags we also use React Router v4 components Link and Route: – – Next we create our pages: – – And finally we create the App…
  • In our example app we used the prop exact in the Route for component HomePage – – That’s because React Router v4 uses inclusive routing instead of exclusive routing used by React Router v3 so without exact property the home component will be rendered with all other components, for example…
  • You can also navigate inside your React application using methods from the history object, for example: – – Which are equivalent to: – – Whenever you want to redirect to another location, you can place component which is when rendered will redirect to the location specified in to prop that…

In this tutorial we are going to get you started with react-router-dom using an example React application showing you how to use different concepts such as Link and NavLink for creating links (instead of anchors) in the React way, Switch and exact for enabling exclusive routing and browser routing history.
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How to use React Lifecycle Methods » Andreas Reiterer

How to use #ReactJS Lifecycle Methods:  by @a_reiterer #JavaScript #Code

  • React components have several “lifecycle methods” that allow us to execute actions (e.g.: fetching data from a server) at particular times.
  • There are three particular stages in the lifecycle of a component, that are important for our lifecycle methods, which I will explain: – – When React creates an instance of a component and inserts it into the DOM (mounting), the following methods are called: – – If props or state…
  • That process is called unmounting and means that the following method is called: – – I hope I could give you a short overview of the life of a React component and the calling order of lifecycle methods.
  • Some people suggest to use it for doing some configuration of the root component that you can only do at runtime (e.g.: setting up a Firebase connection) – – Whenever this method is called, React has already rendered our component and put it into the DOM.
  • This means, it could be possible that the method returns false but React still decides to re-render the component.

Use React lifecycle methods to perform actions on mount, update and unmount of a component. Learn more about e.g. componentDidMount and when to use it
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What’s New With Server-Side Rendering in React 16 – Hacker Noon

What’s New With Server-Side Rendering in #ReactJS 16:  by @xander76 #JavaScript #NodeJS

  • Naturally, this feature is also supported by React 16’s server-side rendering.So, you can now server-render components that look like this:class MyArrayComponent extends React.Component { render() { return [ div key=”1″first element/div, div key=”2″second element/div ]; }}class MyStringComponent extends React.Component { render() { return “hey there”; }}class MyNumberComponent extends React.Component {…
  • To learn more about this feature, read Dan Abramov’s post on the React blog about the change.React 16 SSR Doesn’t Support Error Boundaries or PortalsThere are two new features in the React 16 client-side renderer that are unfortunately not supported in the server-side renderer: Error Boundaries and Portals.
  • If for any reason there’s a mismatch, React raises a warning in development mode and replaces the entire tree of server-generated markup with HTML that has been generated on the client.In React 16, though, the client-side renderer uses a different algorithm to check that the server-generated markup is correct.
  • And when the client-side renderer in React 16 detects a markup mismatch, it only attempts to change the HTML subtree that doesn’t match, rather than the entire HTML tree.Generally, this change shouldn’t have much effect for end users, except for one fact: React 16 doesn’t fix mismatched SSR-generated HTML attributes…
  • This performance optimization means that you will need to make extra sure that you fix any markup mismatch warnings you see in your app in development mode.React 16 Doesn’t Need To Be Compiled For Best PerformanceIn React 15, if you used SSR straight out of the box, performance was less…

There are lots of exciting new bits (most notably the Fiber rewrite), but personally, I’m most excited about React 16’s many improvements that have been made to server-side rendering. Let’s take a…
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react-props-monitor now too with #react16 #reactjs #styledcomponents 😎

react-props-monitor now too with #react16 #reactjs #styledcomponents 😎

  • In-depth checking props in runtime for any React app.
  • PropsMonitor displays exactly which props caused the error based on PropTypes of component.
  • You can define any validation function for props, based on prevProps, nextProps and name of component.
  • ({ nextProps }) { ( . )
  • ; ; }; ({ prevProps, nextProps, name }) { ( name prevProps .

react-props-monitor – In-depth checking props in runtime for any React app.
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Case study of SSR with React in a large e-commerce app – Jakob Lind

Case study of SSR with React in a large e-commerce app  #ReactJS

  • In this case study you will learn: – – In this case study, I present how we have implemented SSR (server side rendering) with React in an e-commerce application for one of Norway’s largest telco brands Telia.
  • What we have learned over the 3 years we have worked with the app is that keeping things simple helps a lot when implementing and maintaining an SSR solution.
  • The theory of SSR is pretty simple: you just render your React components on the backend and send the generated HTML to the client.
  • We create our Redux store with the initialState on the backend like this: – – The initialState variable is also sent to the frontend in a global variable so that the client side app gets the exact same state prefetched.
  • Here are some examples of variables that we guard against on server side: – – The process for knowing when to add the guard is something like: – – We are also careful to only use dependencies that work with SSR.

Setting up SSR (server side rendering) with React is painful. There is no good overview or starting point. Instead, you have to gather pieces of information from googling and do your best to puzzle them together.
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Architecting a Squiggle – Birchbox Unboxed

Architecting a Squiggle  #react #components #css #reactjs

  • It looked like this, and was used to visually emphasize key words or numbers in a block of text.A SquiggleWith the assumption that this coral squiggle would be used only sporadically on a few key pages, we uploaded an image of the squiggle to our CDN and set it as…
  • Our new site, which was built in React, encouraged a component based approach.I created a Squiggle component (later renamed Highlight when it supported shapes other than squiggles) that wrapped any arbitrary content.
  • It accepted props for color, type, and alignment with respect to its content.Highlight type=’wave’ fill=’coral’ alignment=’right’ {title}/HighlightThe component used react-measure to listen to the height of if its children and record it in the component state.
  • ‘wave’ : ‘none’} fill=’coral’ alignment=’right’ {title}/HighlightAn example of conditional highlighting, made possible by the ‘none’ shapeRecently one of my teammates built support for Highlight in our custom Markdown component.
  • No developer time required!This tout was built by our web production team using only Markdown in the CMSWhy I Love itHighlight is one of my favorite components in the Birchbox repository because it makes highlighting text on our site as easy and therapeutically pleasing as highlighting text on a physical page.

When Birchbox rebranded in 2016, our new brand guide included a squiggle. It looked like this, and was used to visually emphasize key words or numbers in a block of text. With the assumption that…
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Debounce Your React and Redux Code to Improve Performance

Debounce Your #ReactJS and Redux #Code to Improve Performance:  by @TreyHuffine #JavaScript

  • Debounce Your React and Redux Code to Improve PerformanceA debounce is a tool that every web developer should have in their kit.
  • Let’s take a look at the individual steps to understand how much we actually saved.After the debounce time expires after the final key press, the first step is to make our API call.
  • Since we have debounced the function that fetches from our API, we only make the request once at the end of typing into the input.There are two things happening here — retrieving projects from the database and then performing heavy calculations to filter and sort the data.
  • By debouncing, we prevent the setState() which serves to significantly reduce the number of times we force React to reconcile and append the list to the DOM.Without a debounce, this component would be almost unusable with such a large amount of data.
  • In addition, you should consider wrapping any interaction that triggers excessive calculations or API calls with a debounce.

A debounce is a tool that every web developer should have in their kit. It improves performance by limiting the number of expensive calculations, API calls, and DOM updates. Although the debounce…
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