拖拽的简单实现

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39

useEffect(() => {
  // 处理移动之类的
  const handleMove = (e) => {
    const left = nodePosRef.current.x;
    const top = nodePosRef.current.y;

    const diffX = e.clientX - startPosRef.current.x;
    const diffY = e.clientY - startPosRef.current.y;

    const targetNodeX = left + diffX;
    const targetNodeY = top + diffY;

    setStyle({ x: targetNodeX, y: targetNodeY });
  };

  const handleUp = () => {
    // 移除事件监听
    window.removeEventListener("mousemove", handleMove);
    window.removeEventListener("mouseup", handleUp);
  };

  const handleDown = (e) => {
    // 初始化的一些操作
    startPosRef.current.x = e.clientX;
    startPosRef.current.y = e.clientY;

    const rect = nodeRef.current.getBoundingClientRect();
    nodePosRef.current.x = rect.left;
    nodePosRef.current.y = rect.top;

    window.addEventListener("mousemove", handleMove);
    window.addEventListener("mouseup", handleUp);
  };

  nodeRef.current.addEventListener("mousedown", handleDown);
  return () => {
    nodeRef.current.removeEventListener("mousedown", handleDown);
  };
}, []);