javascript - What is difference between render function with destructing syntax and with plain empty parameter? -


i coded react , seemed verbose use this.props, googled articles , figured out how , try code it.

class mycomponent extends component {     // usual way     render() {         return <div>{this.props.value}, {this.props.value2}</div>     } }   class mycomponent extends component {     // way of avoding this.props     render({value, value2}){         return <div>{value}, {value2}</div>;     } }  class parentcomponent extends component {     render(){         return <mycomponent value={1} value2={2} />     } }

i not have sense of how handled internally, tried transpile @ https://babeljs.io/repl still difficult understand advantages , disadvantages these syntaxes have.

here summary of questions:

  • is idea use destructuring reduce code?
  • if not, wonder why not use it.

there no benefits other making references said variables shorter. in other words, less typing , better readability.

for more info, have @ this page on mdn:

the destructuring assignment syntax javascript expression makes possible unpack values arrays, or properties objects, distinct variables.

here few other examples, found more common:

desctructuring in stateless functional components:

const mycomponent = ({value, value2}) => (   <div>{value}, {value2}</div> );

destructuring in reactcomponent class:

class mycomponent extends component {   render(){     let {value, value2} = this.props;     return <div>{value}, {value2}</div>;   } }

for stateful components, can same state variables.


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