获取深度嵌套属性值

function getNestedPropertyValue(obj, propertyPath) {
  // 将属性路径拆分为数组
  const properties = propertyPath.split('.');
  
  // 递归函数来获取属性值
  function getProperty(obj, properties) {
    const property = properties.shift();
    
    if (obj.hasOwnProperty(property)) {
      if (properties.length === 0) {
        return obj[property];
      } else {
        return getProperty(obj[property], properties);
      }
    }
    
    return undefined;
  }
  
  return getProperty(obj, properties);
}

const data = {
  a: {
    b: {
      c: 123
    }
  }
};

const value = getNestedPropertyValue(data, 'a.b.c');
console.log(value); // 输出 123