protobuf入门教程(三):常用序列化/反序列化接口

时间:2021-07-02 16:04:43

C数组的序列化和反序列化

#include "addressbook.pb.h"
#include <iostream>
using namespace std;

/*
//C数组的序列化和序列化API
//在/usr/local/include/google/目录下,查找包含"SerializeToArray"所有的文件,同时打印所在行
//sudo grep "SerializeToArray" -r /usr/local/include/google/ -n

bool SerializeToArray(void* data, int size) const; //序列化
bool ParseFromArray(const void* data, int size); //反序列化
*/

char buf[1024];
int len;

void set_person()
{
Person obj;
obj.set_name("mike");
obj.set_id(1);
*obj.mutable_email() = "xxx@qq.com"; //obj.set_email("xxx@qq.com");

len = obj.ByteSize(); //获取长度
cout << "len = " << len << endl;

obj.SerializeToArray(buf, len);//序列化,obj成员保存在buf中
}

void get_person()
{
Person obj;
obj.ParseFromArray(buf, len); //反序列化,buf的内容设置给obj的成员

cout << "name = " << obj.name() << endl;
cout << "id = " << obj.id() << endl;
cout << "email = " << obj.email() << endl;
}

int main()
{
// Verify that the version of the library that we linked against is
// compatible with the version of the headers we compiled against.
GOOGLE_PROTOBUF_VERIFY_VERSION;

set_person(); //序列化
get_person(); //反序列化

// Optional: Delete all global objects allocated by libprotobuf.
google::protobuf::ShutdownProtobufLibrary();

return 0;
}

protobuf入门教程(三):常用序列化/反序列化接口

C++ String的序列化和反序列化

//bool SerializeToString(string* output) const; 
//bool ParseFromString(const string& data);

string str; //全局变量

void set_person()
{
Person obj;
obj.set_name("mike");
obj.set_id(1);
obj.set_email("xxx@qq.com");
//*obj.mutable_email() = "xxx@qq.com";

obj.SerializeToString(&str); //序列化,obj成员的内容设置给str
}

void get_person()
{
Person obj;
obj.ParseFromString(str); //反序列化, str内容设置给obj的成员

cout << "name = " << obj.name() << endl;
cout << "id = " << obj.id() << endl;
cout << "email = " << *obj.mutable_email() << endl;
}

文件描述符序列化和反序列化

//bool SerializeToFileDescriptor(int file_descriptor) const; 
//bool ParseFromFileDescriptor(int file_descriptor);

void set_person()
{
Person obj;
obj.set_name("mike");
obj.set_id(1);
obj.set_email("xxx@qq.com");
//*obj.mutable_email() = "xxx@qq.com";

//O_CREAT: 新建文件, O_TRUNC:清空文件,O_RDWR:读写
int fd = open("./pb.xxx", O_CREAT | O_TRUNC | O_RDWR, 0644);
if (fd <= 0)
{
perror("open");
exit(0);
}

obj.SerializeToFileDescriptor(fd); //序列化,obj成员的内容写入fd所关联的文件中

close(fd); //关闭文件
}

void get_person()
{
int fd = open("./pb.xxx", O_RDONLY); //O_RDONLY: 只读方式
if (fd <= 0)
{
perror("open");
exit(0);
}

Person obj;
obj.ParseFromFileDescriptor(fd); //反序列化, fd文件内容设置给obj的成员
close(fd); //关闭文件

cout << "name = " << obj.name() << endl;
cout << "id = " << obj.id() << endl;
cout << "email = " << *obj.mutable_email() << endl;
}

C++ stream 序列化和反序列化

//bool SerializeToOstream(ostream* output) const; 
//bool ParseFromIstream(istream* input);

void set_person()
{
Person obj;
obj.set_name("mike");
obj.set_id(1);
obj.set_email("xxx@qq.com");
//*obj.mutable_email() = "xxx@qq.com";

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_person()
{
Person obj;
fstream input("./pb.xxx", ios::in | ios::binary);
obj.ParseFromIstream(&input); //反序列化
input.close(); //关闭文件

cout << "name = " << obj.name() << endl;
cout << "id = " << obj.id() << endl;
cout << "email = " << *obj.mutable_email() << endl;
}

本教程源代码下载地址:http://download.csdn.net/detail/tennysonsky/9884275

本文转自:http://blog.csdn.net/sealyao/article/details/6940245