ReactJS - how to pass "global" data to deeply nested child components?

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How do people typically approach having "global" data in a React application?

For example, say I have the following data for a user once they're logged into my app.

user: {
  email: 'test@user.com',
  name: 'John Doe'
}

This is data that almost any component in my app might like to know about - so it could either render in a logged in or logged out state, or perhaps display the users email address if logged in.

From my understanding, the React way of accessing this data in a child component is for a top level component to own the data, and pass it to child components using properties, for example:

<App>
  <Page1/>
  <Page2>
    <Widget1/>
    <Widget2 user={user}/>
  </Page2>
</App>

But this seems unwieldy to me, as that would mean I'd have to pass the data through each composite, just to get it to the child that needed it.

Is there a React way of managing this type of data?

Note: This example is very simplified - I like to wrap intents up as composites so implementation details of entire UI features can be drastically changed as I see fit.

EDIT: I'm aware that by default, calling setState on my top level component would cause all child components to be re-rendered, and that in each child component I can render using whatever data I like (e.g. global data, not just state or props). But how are people choosing to notify only certain child components that they should be rendered?


Handling Events – React, With JSX you pass a function as the event handler, rather than a string. For example, the HTML: <button onclick="activateLasers()"> Activate Lasers </button​>. Pass event handlers and other functions as props to child components: < button onClick = { this . handleClick } > If you need to have access to the parent component in the handler, you also need to bind the function to the component instance (see below).


Use the React Context Property This is specifically for passing global data sets down the chain without explicitly forwarding them. It does complicate your Component lifecycle functions though, and note the cautions offered on the page I've linked.

Composition vs Inheritance – React, We recommend that such components use the special children prop to pass children elements directly into their output: function FancyBorder(props) { return  In order to pass values from first component to second component we have to include second (child) component inside the first (parent) component. Step 4: Accessing passed values (props) from component 2 All the values pass from parent component stored on props variable of child component or component 2.


What's wrong with just passing data all the way down the component chain via rendering all children with {...restOfProps}?

render(){
  const {propIKnowAbout1, propIKnowAbout2, ...restOfProps} = this.props;
  return <ChildComponent foo={propIKnowAbout1} bar={propIKnowAbout2} {...restOfProps}/>
}

Context – React, Context provides a way to pass data through the component tree without having to pass props down manually at every level. In a typical React application, data  You only need to define key to the span so use it as key={props.index}. It should eliminate the warning. According to React docs, a key should be provided for list component items. You only need pass the key to react component, you don't need to use it in the component, like access the key with props.key.


You can use the React Context API for passing global data down to deeply nested child components. Kent C. Dodds wrote an extensive article on it on Medium React’s ⚛️ new Context API. It'll help in getting a better understanding of how to use the API.

How to pass props to components in React, How to pass Props from child to parent Component? Props can be state, props, or derived properties; React Props and Code Style; React props  Refs and the DOM. Refs provide a way to access DOM nodes or React elements created in the render method. In the typical React dataflow, props are the only way that parent components interact with their children. To modify a child, you re-render it with new props.


Passing data between different component levels in Reactjs, Passing data between components of different levels is important and also a trickier thing to do in Reactjs. The data flow for some directions is  Try it on CodePen. React elements like <Contacts /> and <Chat /> are just objects, so you can pass them as props like any other data. This approach may remind you of “slots” in other libraries but there are no limitations on what you can pass as props in React.


ReactJS Basics - #6 Passing Data with Props, How to pass state between components in reactjs (Full Code). Tagged with react, javascript, code, frontend. Pass a string as the className prop: It is common for CSS classes to depend on the component props or state: If you often find yourself writing code like this, classnames package can simplify it. Yes, see the docs on styling here. CSS classes are generally better for performance than inline styles. “CSS-in-JS” refers to a pattern where CSS


How to pass state between components in reactjs, When learning ReactJS, we often hear the term props. While it may sound confusing, props are nothing but objects which are used to pass data  We pass our ref down to <FancyButton ref={ref}> by specifying it as a JSX attribute. React passes the ref to the (props, ref) => function inside forwardRef as a second argument. We forward this ref argument down to <button ref={ref}> by specifying it as a JSX attribute. When the ref is attached,