Analysis of implementation methods from protobuf C ++ serialize to char *

Protobuf demoProgramYes

The C ++ version of protubuf has several serialize and unserialize methods:

Method 1:

The official demo program uses

CopyCode The Code is 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 uses fstream to compress data sequences (reverse sequences) into disk files.

If you want to sequence to char * and transmit it through socket, you can use:

Method 2:

Copy code The Code is as follows: int size = address_book.bytesize ();

Void * buffer = malloc (size );

Address_book.serializetoarray (buffer, size );

Method 3:

Copy code The Code is as follows: Use ostringstream,

STD: ostringstream stream;

Address_book.serializetoostream (& stream );

String text = stream. STR ();

Char * ctext = string. c_str ();