我想為 40 個 div 創建多個引用而不使用React.createRef(). 但我無法為我的引用創建動態變量名稱。我正在使用下面的代碼來創建參考。const displayXmasTreeParts = () => Array(40).fill().map((el, index) => (  <div className={`xmasTreePart${randomClass}`} key={`part${index}`}      ref={el => [this.el`${index}`] = el}/>);const handleClick = () => this.el5.classList.add(`new-class`);render() {  return (    <div className="xmasTree">      {this.displayXmasTreeParts()}    </div>    <button className="SetUpTree" onClick={this.handleClick}>Click here to reveal Our Xmas Tree</button>)}我也嘗試過這個ref={el => `this.el${index}` = el}但Invalid left-hand side in assignment expression在這兩種情況下都會出現此錯誤。