在週期中使用switch-case

switch(this.state.color){
     case "1":return <img src={gift1}/>; break;
     case "2":return <img src={gift2}/>; break;
     case "3":return <img src={gift3}/>; break;
     default:return null;
}

在render中使用switch-case

<div>
    {( ()=>{
         switch
 
(this.state.color){
             case "1":return <img src={gift1}/>; break;
             case "2":return <img src={gift2}/>; break;
             case "3":return <img src={gift3}/>; break;
             default:return null;
          }
        }
    )()}
</div>