16.1. Network Address Management

There are two types of classes for managing a network address(an IP address, a domain, and a port number).

Table 16.1. Network Address Management Classes

Class Name	Description
`SFXInetAddress`	Class for managing an IP address and a domain.
`SFXSocketAddress`	Class for managing an IP address, a domain, and a port number

To resolve the domain manually, use the SFXInetAddress::Resolve function.

	About MIF File Setting
	Never forget to turn on the Network option in the MIF file setting of privilege level.

Example 16.1. Define the IP address, domain, and port number

SFXSocketAddress address1("127.0.0.1");          // IP address (port number: 0)
SFXSocketAddress address2("127.0.0.1:80");       // IP address and port number
SFXSocketAddress address3("www.example.com:80"); // Domain and port number

Example 16.2. Set the address

SFXSocketAddress address;

address.Set("www.example.com:80"); 
address.Set("http://www.example.com:80/dir1/dir2/index.html");
address.Set("http://user@127.0.0.1:80/dir1/");

The string can be set in various formats to the argument of SFXSocketAddress::Set funtion or the constructor, but strings other than domain and port number are ignored.

Example 16.3. Set the address: in case of TCP Communication

// erro handling is omitted for simplified explanation
SFXSocketAddress address("www.example.com:80");

SFXTCPSocket _socket;

// initial processing
_socket.Open();

// address is automatically resolved by passing domain argument of SFXSocketAddress type
// connection establishment will be notified to OnConnect function
_socket.Connect(address, CALLBACK_FUNCTION(OnConnect));

If SFXTCPSocket class is used in TCP communication, the address is automatically resolved if domain name is set by SFXSocketAddress.

Example 16.4. The method to resolve the domain

// SFXSocketAddress instance is defined as class member variable for the callback function
class MyClass {
private:
    SFXSocketAddress _address;
public:
    Void Start(Void);
    CALLBACK_DECLARE_SFXSOCKETADDRESS(ResolveCallback);
};

Void MyClass::Start(Void)
{
    SFCError error;

    // set domain and port number
    if ((error = _address.Set("www.example.com:80")) == SFERR_NO_ERROR) {
        // resolve domain ( completion of resolving domain will be notified to ResolveCallback function )
        error = _address.Resolve(CALLBACK_FUNCTION(ResolveCallback));
    }
    if (error != SFERR_NO_ERROR) {
        // error handling (callback function will not be called)
        ...
    }
}

// callback funtion notified of completion of resolving domain
CALLBACK_IMPLEMENT_SFXSOCKETADDRESS(MyClass, ResolveCallback, error)
{
    SFXAnsiString ip;
    SInt32 i;

    for (i = 0; i < _address.GetCount(); ++i) {
        ip = _address.GetIP(i);      // get result
        TRACE("%s",ip.GetCString()); // display result
    }
}

Since the domain may be converted into multiple IP addresses after resolving, get the specific IP address by using its index number.

	SFXSocketAddress Instance
	If the `SFXSocketAddress` instance is released before the callback function is called, program will not work correctly.