How do i call function before page is loaded in react

Question

i'm trying to cal a mutation to verify some information in the backend before the page is loaded in react is there any way I can trigger the function when the page is about to load or is loading

Answer 1

You can can have a isLoading state set to true by default. Make necessary calls in the useEffect hook and after the calls setIsLoading to false. In the UI part you can do conditional rendering ie if isLoading true do not display anything, else display the UI

Answer 2

Check this

https://reactjs.org/docs/react-component.html https://www.pluralsight.com/guides/how-to-use-componentwillmount

import React from 'react';

export default class App extends React.Component {
    render() {
        return <div>
            Content
        </div>
    componentDidMount() {
        // component mounted
    }
    componentwillMount() {
        // component will be mounted
    }
}