TIL: How to Pass Props to React Router

06/16/20191 Min Read — In React.js, JavaScript

Just a short note: Today I learned that you shouldn't pass props to React Router with the component attribute, but with render.

From the Docs:

When you use component (instead of render or children, below) 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. This results in the existing component unmounting and the new component mounting instead of just updating the existing component. When using an inline function for inline rendering, use the render or the children prop (below).

render: func
This allows for convenient inline rendering and wrapping without the undesired remounting explained above.Instead of having a new React element created for you using the component prop, you can pass in a function to be called when the location matches. The render prop receives all the same route props as the component render prop.

const FadingRoute = ({ component: Component, ...rest }) => (
<Route {...rest} render={props => (
<FadeIn>
<Component {...props}/>
</FadeIn>
)}/>
)
<FadingRoute path="/cool" component={Something}/>

I found an excellent explanation on Tyler McGinnis's blog: Pass props to a component rendered by React Router.