限定修饰符说明
repeated 代表可重复,我们可以理解为数组:
syntax = "proto3";//指定版本信息,不指定会报错
message Person //message为关键字,作用为定义一种消息类型
{
string name = 1; //姓名
int32 id = 2; //id
string email = 3; //邮件
}
message AddressBook
{
repeated Person people = 1;
}
字段API
而对于字段修饰符为repeated的字段生成的函数,则稍微有一些不同,如people字段,则编译器会为其产生如下的代码:
int people_size() const;
void clear_people();
const ::Person& people(int index) const;
::Person* mutable_people(int index);
::Person* add_people();
::google::protobuf::RepeatedPtrField< ::Person >* mutable_people();
const ::google::protobuf::RepeatedPtrField< ::Person >&
测试程序
void set_addressbook()
{
AddressBook obj;
Person *p1 = obj.add_people(); //新增加一个Person
p1->set_name("mike");
p1->set_id(1);
p1->set_email("[email protected]");
Person *p2 = obj.add_people(); //新增加一个Person
p2->set_name("jiang");
p2->set_id(2);
p2->set_email("[email protected]");
Person *p3 = obj.add_people(); //新增加一个Person
p3->set_name("abc");
p3->set_id(3);
p3->set_email("[email protected]");
fstream output("pb.xxx", ios::out | ios::trunc | ios::binary);
bool flag = obj.SerializeToOstream(&output);//序列化
if (!flag)
{
cerr << "Failed to write file." << endl;
return;
}
output.close();//关闭文件
}
void get_addressbook()
{
AddressBook obj;
fstream input("./pb.xxx", ios::in | ios::binary);
obj.ParseFromIstream(&input); //反序列化
input.close(); //关闭文件
for (int i = 0; i < obj.people_size(); i++)
{
const Person& person = obj.people(i);//取第i个people
cout << "第" << i + 1 << "个信息\n";
cout << "name = " << person.name() << endl;
cout << "id = " << person.id() << endl;
cout << "email = " << person.email() << endl <<
编译运行结果:
标签:set,obj,入门教程,people,修饰符,ios,Person,repeated,const From: https://blog.51cto.com/u_3002289/5720700