only render component if not null react code example
Example 1: react if statement
render() {
const isLoggedIn = this.state.isLoggedIn;
return (
<div>
The user is <b>{isLoggedIn ? 'currently' : 'not'}</b> logged in. </div>
);
}
Example 2: conditional rendering react
import React, { Component } from 'react';
// @params [] * denotes optional param (we will need to use conditional rendering for some of these)
// [type](Bulma CSS class): Hero type, focuses on the base styling
// size(Bulma CSS Class): The size of the hero, small, medium, large, etc...
// heading: The main heading
// [subheading]: The subheading if desired
// [alignment](Bulma CSS Class): Aligns the content horizontally
// This Simple HeroComponent is bases upon the following
// https://bulma.io/documentation/layout/hero/
export class HeroComponent extends Component
{
render() {
return (
// The following ternary simply applies a class if it has been specified
<section className={"hero" + (this.props.type ? " " + this.props.type + " " : " ") + this.props.size}>
<div className="hero-body">
// Again, another ternary applying a class... blah blah blah....
<div className={"container" + this.props.alignment ? " " + this.props.alignment : ""}>
<h1 className="title">{this.props.heading}</h1>
// So, to answer the question...
// The following is one way to do conditional rendering, probably the simplest and cleanest
// If this.props.subheading exists, render <h2 .. />
{this.props.subheading && <h2 className="subtitle">{this.props.subheading}</h2>}
</div>
</div>
</section>
)
}
}