' Visual Basic
Dim cmd As ULCommand = new ULCommand( _
    "SELECT * FROM Departments", conn _
)
Dim res As IAsyncResult res = _
    cmd.BeginExecuteReader()
' Perform other work
' This blocks until the command completes.
Dim reader As ULDataReader = _
    cmd.EndExecuteReader( res )

// C#
ULCommand cmd = new ULCommand(
    "SELECT * FROM Departments", conn
);
IAsyncResult res = cmd.BeginExecuteReader();

// Perform other work
// This blocks until the command completes
ULDataReader reader = cmd.EndExecuteReader( res );

' Visual Basic
Dim cmd As ULCommand = new ULCommand( _
    "SELECT * FROM Departments", conn _
)
Dim res As IAsyncResult res = _
    cmd.BeginExecuteReader()
While( !res.IsCompleted )
    ' Perform other work
End While
' This blocks until the command completes.
Dim reader As ULDataReader = _
    cmd.EndExecuteReader( res )



// C#
ULCommand cmd = new ULCommand(
    "SELECT * FROM Departments", conn
);
IAsyncResult res = cmd.BeginExecuteReader();
while( !res.IsCompleted ) {
    // Perform other work.
}
// This blocks until the command completes.
ULDataReader reader = cmd.EndExecuteReader( res );

' Visual Basic
Dim cmd As ULCommand = new ULCommand( _
    "SELECT * FROM Departments", conn _
)
Dim res As IAsyncResult res = _
    cmd.BeginExecuteReader()
' Perform other work.
Dim wh As WaitHandle = res.AsyncWaitHandle
wh.WaitOne()
' This does not block because the command is finished.
Dim reader As ULDataReader = _
    cmd.EndExecuteReader( res )

// C#
ULCommand cmd = new ULCommand(
    "SELECT * FROM Departments", conn
);
IAsyncResult res = cmd.BeginExecuteReader();
// Perform other work.
WaitHandle wh = res.AsyncWaitHandle;
wh.WaitOne();
// This does not block because the command is finished.
ULDataReader reader = cmd.EndExecuteReader( res );

' Visual Basic
Private Sub callbackFunction(ByVal ar As IAsyncResult)
    Dim cmd As ULCommand = _
        CType(ar.AsyncState, ULCommand)
    ' This won't block since the command has completed.
    Dim reader As ULDataReader = cmd.EndExecuteReader()
End Sub

' Elsewhere in the code
Private Sub DoStuff()
    Dim cmd As ULCommand = new ULCommand( _
        "SELECT * FROM Departments", conn _
    )
    Dim res As IAsyncResult = _
        cmd.BeginExecuteReader( _
        callbackFunction, cmd _
    )
    ' Perform other work.  The callback function
    ' is called when the command completes.
End Sub

// C#
private void callbackFunction( IAsyncResult ar )
{
    ULCommand cmd = (ULCommand) ar.AsyncState;
    // This won't block since the command has completed.
    ULDataReader reader = cmd.EndExecuteReader();
}

// Elsewhere in the code.
private void DoStuff()
{
    ULCommand cmd = new ULCommand(
        "SELECT * FROM Departments", conn
    );
    IAsyncResult res = cmd.BeginExecuteReader(callbackFunction, cmd);

    // Perform other work.  The callback function
    // is called when the command completes.
}