Platform SDK: DirectX

Step 3: Create or Join a Session

[C++]

This tutorial pertains only to applications written in Visual Basic. See DirectPlay C/C++ Tutorials

[Visual Basic]

On the frmSessions form of the Memory sample, the user has the choice of joining a listed session or creating a new one.

In both cases the procedure is the same: describe the session in a DirectPlaySessionData object, then pass this object to DirectPlay4.Open.

The following code, from the cmdCreate_Click method in frmCreateGame, creates a new game that will accept from two to four players, as specified by the choice of option buttons:

Dim SessionData As DirectPlaySessionData
 
Set SessionData = gObjDPlay.CreateSessionData
.
.
.
  ' Set number of players
If Option1.Value = True Then
    Call SessionData.SetMaxPlayers(2)
ElseIf Option2.Value = True Then
    Call SessionData.SetMaxPlayers(3)
Else
    Call SessionData.SetMaxPlayers(4)
End If
 
' Finish describing the session
Call SessionData.SetSessionName(txtGameName.Text)
Call SessionData.SetGuidApplication(AppGuid)
Call SessionData.SetFlags(DPSESSION_MIGRATEHOST)
 
' Create (and join) the session.
' Failure can result from the user cancelling out of the service
' provider dialog. In the case of the modem, this is the "answer"
' dialog.
 
  On Error GoTo FAILEDOPEN
  Call gObjDPlay.Open(SessionData, DPOPEN_CREATE)
.
.
.
End Sub

Joining a session is a bit simpler, because the application just has to retrieve the session description from the enumeration, as in the cmdJoin_Click method of frmSessions:

Dim SessionData As DirectPlaySessionData
 
Set SessionData = gObjDPEnumSessions.GetItem( _
        lstSessions.ListIndex + 1)
On Error GoTo NOSESSION
Call gObjDPlay.Open(SessionData, DPOPEN_JOIN)

Next: Step 4: Create a Player