如何将嵌套对象转换为字符串索引对象

function convertNestedObjectToStringIndex(obj) {
  if (typeof obj !== 'object' || obj === null || Array.isArray(obj)) {
    return obj;
  }

  const result = {};

  for (const key in obj) {
    if (obj.hasOwnProperty(key)) {
      const value = obj[key];

      if (typeof value === 'object') {
        result[key] = convertNestedObjectToStringIndex(value);
      } else {
        result[key] = value;
      }
    }
  }

  return result;
}

// 示例用法
const nestedObj = {
  name: 'John',
  age: 30,
  address: {
    street: '123 Main St',
    city: 'New York',
    country: 'USA'
  }
};

const stringIndexObj = convertNestedObjectToStringIndex(nestedObj);
console.log(stringIndexObj);