web/src/pages/flow/canvas/edge/index.tsx

import {
  BaseEdge,
  EdgeLabelRenderer,
  EdgeProps,
  getBezierPath,
} from 'reactflow';
import useStore from '../../store';

import { useMemo } from 'react';
import styles from './index.less';

export function ButtonEdge({
  id,
  sourceX,
  sourceY,
  targetX,
  targetY,
  sourcePosition,
  targetPosition,
  style = {},
  markerEnd,
  selected,
}: EdgeProps) {
  const deleteEdgeById = useStore((state) => state.deleteEdgeById);
  const [edgePath, labelX, labelY] = getBezierPath({
    sourceX,
    sourceY,
    sourcePosition,
    targetX,
    targetY,
    targetPosition,
  });

  const selectedStyle = useMemo(() => {
    return selected ? { strokeWidth: 1, stroke: '#1677ff' } : {};
  }, [selected]);

  const onEdgeClick = () => {
    deleteEdgeById(id);
  };

  return (
    <>
      <BaseEdge
        path={edgePath}
        markerEnd={markerEnd}
        style={{ ...style, ...selectedStyle }}
      />
      <EdgeLabelRenderer>
        <div
          style={{
            position: 'absolute',
            transform: `translate(-50%, -50%) translate(${labelX}px,${labelY}px)`,
            fontSize: 12,
            // everything inside EdgeLabelRenderer has no pointer events by default
            // if you have an interactive element, set pointer-events: all
            pointerEvents: 'all',
          }}
          className="nodrag nopan"
        >
          <button
            className={styles.edgeButton}
            type="button"
            onClick={onEdgeClick}
          >
            ×
          </button>
        </div>
      </EdgeLabelRenderer>
    </>
  );
}