Are you using experimental syntax in React JS?

Question

React

Good afternoon, I started to learn React JS and a question arose.
Is it possible to use this syntax to manage state?

state = {
            class: 'off',
            label: 'Нажми'
        }
        press = () => {
            let className = (this.state.class==="off")?"on":"off";
            let label = (this.state.label === 'Нажми')?'нажми еще раз?':'Нажми';
            this.setState({class: className, label: label});
        }
        render() {
            return <button onClick={this.press} className={this.state.class}>{this.state.label}</button>;
        }

I like this option better, but still wanted to know the opinion of experienced developers.