获取数组项的附近对象

function getNearbyItems(array, index) {
  // 检查索引是否有效
  if (index < 0 || index >= array.length) {
    return { previous: undefined, next: undefined };
  }

  // 获取前一个元素
  const previousItem = array[index - 1] !== undefined ? array[index - 1] : undefined;
  // 获取后一个元素
  const nextItem = array[index + 1] !== undefined ? array[index + 1] : undefined;

  return { previous: previousItem, next: nextItem };
}

// 示例数组
const items = ['Apple', 'Banana', 'Cherry', 'Date', 'Elderberry'];

// 获取索引为2的元素的附近对象
const nearbyItems = getNearbyItems(items, 2);
console.log(nearbyItems); // 输出: { previous: 'Banana', next: 'Date' }

function getNearbyItems(array, index) {
  if (index < 0 || index >= array.length) {
    return { previous: undefined, next: undefined };
  }
  // ... 其余代码不变
}