鼠标为中心缩放的简单实现

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// ...
useEffect(() => {
  const handleScale = (e) => {
    // 这里用到了阻止默认行为
    e.preventDefault();

    const cursorX = e.clientX;
    const cursorY = e.clientY;

    // == 这里以下都是纯计算逻辑啦
    const posRateX = (cursorX - initLeft) / initWidth;
    const posRateY = (cursorY - initTop) / initHeight;

    const currentHeight = initHeight - e.deltaY;

    // 保证 width 和 height 变化的比例一样
    const currentWidth = initWidth * (currentHeight / initHeight);

    const diffX = currentWidth * posRateX;
    const diffY = currentHeight * posRateY;

    const targetNodeX = cursorX - diffX;
    const targetNodeY = cursorY - diffY;

    setStyle({
      x: targetNodeX,
      y: targetNodeY,
      width: currentWidth,
      height: currentHeight,
    });
    // 再记录位置和尺寸参数
    // ...
  };

  // 这里传了第三个参数 `{ passive: false }`
  window.addEventListener("mousewheel", handleScale, {
    passive: false,
  });
  return () => {
    window.removeEventListener("mousewheel", handleScale, {
      passive: false,
    });
  };
}, []);