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Component Lifecycle / useEffect()

Why do we not need more .html pages in a multi-page React app?

It takes advantage of HTML's popularity and strength as the most popular programming language, by letting you use a very similar syntax to HTML to build interfaces and add dynamic features to it using JavaScript.

If we wanted a component to show up on every page, where would we put it and why?

Inside the (BrowserRouter /), outside a (Route)

What does routing do with the components that were rendered when a new route is requested

One way to do would be to pass the component prop an inline function. When you use component, the router uses React. createElement to create a new React element from the given component. That means if you provide an inline function to the component prop, you would create a new component every render.

What does props.children contain?

display whatever you include between the opening and closing tags when invoking a component. This component contains an (img) that is receiving some props and then

How do useState() and this.setState() differ?

setState() does not immediately mutate this. state but creates a pending state transition. Accessing this. state after calling this method can potentially return the existing value.

  • State Hook : A Hook is a special function that lets you “hook into” React features. For example, useState is a Hook that lets you add React state to function components. We'll learn other Hooks later.

  • Mounting and Un-Mounting : Mounting a file system attaches that file system to a directory (mount point) and makes it available to the system. ... The root ( / ) file system is always mounted. Any other file system can be connected or disconnected from the root ( / ) file system.

effects hook

Using the Effect Hook