如何在反应组件中使用解构

Question

I have done lots of reading online and just cant get destructuring into my head, well sort of.

//before destructuring
function me(details){
  console.log('My name is ' + details.name + ' and I work for ' + details.company);
}
//after destructuring
function me({ name, company }){
  console.log('my name is ' + name + ' and i work for ' + company);
}

me({
  name: 'Rich',
  age: 34,
  city: 'London',
  company: 'Google'
})

I've written this and this makes sense but one thing I dont get is the following in react.

if you do this:

export default ({ name }) => <h1>Hello {name}!</h1>;

<Hello name="CodeSandbox" />

why cant i do this:

export default ( name ) => <h1>Hello {name}!</h1>;

removing the {} in the function parameter?

if someone sees what im doing wrong please can they explain this?

im used to functions like so:

functionA (a) => { // do something with the parameter a }

not sure about the curlys {} inside the parameters

Answer 1

export default (name) => <h1>Hello {name}!</h1>;

won't work because for any component, there is only one argument which is props

So in its longest form you could write

export default (props) => {
  return <h1>Hello {props.name}!</h1>;
}

which can be shortened (using destructuring) as:

export default (props) => {
  const {name} = props; // Extract name from props using destructuring
  return <h1>Hello {name}!</h1>;
}

which can be shortened (using destructuring at parameter level) as:

export default ({name}) => { // Extract name directly here
  return <h1>Hello {name}!</h1>;
}

which can be shortened (removing the function body curly braces) as:

export default ({name}) => <h1>Hello {name}!</h1>;