Analysis of implementation method based on Protobuf C + + serialize to char* _c language

Protobuf's demo program is

The C + + version of Protubuf has several serialize and Unserialize methods:

Method One:

The official demo program uses the

Copy Code code as follows:

Write The new Address book back to disk.

FStream output (argv[1], ios::out | ios::trunc | ios::binary);

if (!address_book. Serializetoostream (&output)) {

Cerr << "Failed to write Address Book." << Endl;

return-1;

}

Read the existing address book.

FStream input (argv[1], ios::in | ios::binary);

if (!input) {

cout << argv[1] <<: File not found. Creating a new file. "<< Endl;

else if (!address_book. Parsefromistream (&input)) {

Cerr << "Failed to parse Address Book." << Endl;

return-1;

}

The above is fstream, the data sequence (reverse sequence) in the disk file.

And if you want to sequence to char * and transfer through the socket, you can use:

Method Two:

Copy Code code as follows:

int size = Address_book. ByteSize ();

void *buffer = malloc (size);

Address_book. Serializetoarray (buffer, size);

Method Three:

Copy Code code as follows:

Using Ostringstream,

Std::ostringstream stream;

Address_book. Serializetoostream (&stream);

string text = Stream.str ();

char* Ctext = String.c_str ();