react 按下鼠标移动监听不到onMouseMove事件，松开时也监听不到onMouseUp

Question

<img alt="" src={Url}  onMouseDown={handleMouseDown}  onMouseMove={handleMouseMove}  onMouseUp={handleMouseUp}/>事件  let flag = false  const handleMouseDown = () => {    flag = true    console.log('down')  }  const handleMouseMove = () => {    if (flag) {      console.log('move')    }  }  const handleMouseUp = () => {    console.log('up')    flag = false  }想要实现从图片中选取一个区域，当按下鼠标时可以监听到，按着移动和松开都监听不到。在原地按下松开可以监听到。请大家帮忙看看