Hoffmann Hoffmann Add a comment. Active Oldest Votes. There are three related kinds of thing involved here, with their own names: Components Component instances Elements This is slightly surprising, since if you're used to other UI frameworks you might expect that there'd only be two kinds of thing, roughly corresponding to classes like Widget and instances like new Widget.
To illustrate this, consider this code: import React from 'react'; import ReactDOM from 'react-dom'; import '. It's not an instance of MyComponent ; rather, it's simply a description of the component instance to be created. It's an object with key , props , ref and type properties. Here, key and ref are null , props is an empty object, and type is MyComponent.
An instance of MyComponent gets created and, in the example above, logs itself from its constructor when element gets rendered. Improve this answer. Mark Amery Mark Amery k 62 62 gold badges silver badges bronze badges.
To sum up, Component can be used to create an Instance and when that Instance is rendered an Element is created. Any thoughts about React Node? How is that not one-to-one relationship between component instance and element? Are you suggesting that an element can describe multiple component instances? Or that multiple elements can describe the same component instance? Otherwise, they are by definition one-to-one related.
Andy Multiple elements can describe the same component instance. Not simultaneously, but over the course of that instance's lifetime.
Show 4 more comments. Rich Warrior 1, 7 7 silver badges 17 17 bronze badges. I think user 's answer says the same. I am no expert but somehow common sense tells me that this is the only meaningful interpretation, after a bit of thinking This answer is from a long time ago and the VDOM structure and its access would have changed. I'll have to update it I think, but I haven't worked with React since then, so I'll have to research first. If anyone wants to moderate this or put in comments, I'd be most happy!
Mark Amery k 62 62 gold badges silver badges bronze badges. It is a "lifting" - sort of like an abstract syntax tree of a programming language. Or a Monad. To put it simply. With a function component, this element is the object that the function returns. R React elements are not what we see in the browser. React elements can have other type properties other than native HTML elements.
We know the following: A react element describes what we want to see on the screen. React is good with this in these ways: React can create and destroy these element without much overhead. The JS objects are lightweight and low-cost. React can diff an object with the previous object representation to see what has changed. React can update the actual DOM specifically where the changes it detected occurred. This has some performance upsides. We can create an object representation of a DOM node aka React element using the createElement method.
React Components A component is a function or a Class which optionally accepts input and returns a React element. Class-Based Components Class syntax is one of the most common ways to define a React component. Supersonic vs. Gazelle vs. Jem vs. Mouse vs. Lubuntu vs.
You vs. Virtual vs. Featured Comparisons Guidence vs. Togather vs. Maintenance vs. Brachycardia vs. Villainize vs. Catagory vs. Correspondance vs. Incentivise vs. Turnip vs. Sign up Sign in. English US. Question about English US. What is the difference between elements and components? Feel free to just provide example sentences. The flute, a component part of the organ, is one of the most ancient of musical instruments.
Avowe is all one word, though its component parts were often written apart. If the web is a braced web, then the vertical component of the stress in the web bars cut by the section must be equal to S.
In such cases it is extremely likely that an ion of the salt in question forms a complex ion with a component of the solution. The sign always denotes the character of the charge on the first component written in the subscript to. New Word List Word List. Save This Word!
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