public OnPlayerPickUpPickup(playerid,pickupid)
{
    if(somepickup == pickupid)
    {
          switch(random(2)) // random(2) can produce either the number 0 or 1
          {
                   case 0: SendClientMessage(playerid,0xFF0000FF,"Sorry, the heart is bad");
                   case 1: SendClientMessage(playerid,0x00FF00FF,"Yeee this heart is cool and all");
          }
    }
}

If(pickupid == someid)
{
    If(HeartType(playerid)==0)
    {
         //Reduce health or whatever you want to do
    }
    Else
    {
        Code here
    }
}

F:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx(3582) : warning 205: redundant code: constant expression is zero
F:\xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx : error 012: invalid function call, not a valid address
F:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx(3584) : warning 215: expression has no effect
F:\xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx(3584) : error 001: expected token: ";", but found ")"
F:\xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx(3584) : error 029: invalid expression, assumed zero
F:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx(3584) : fatal error 107: too many error messages on one line

Compilation aborted.Pawn compiler 3.2.3664          Copyright (c) 1997-2006, ITB CompuPhase


4 Errors.

public OnPlayerPickUpPickup(playerid,pickupid)
{
    if(1240 == 1)
    {
        if(HeartType(playerid) == 0)
        {
         SendClientMessage(playerid, COLOR_GREY, "Bad");
        }
         else if(HeartType(playerid) == 1)
        {
         SendClientMessage(playerid, COLOR_GREY, "Good ");
        }
    }
    return 1;
}

if(1240 == 1)

new HeartPickup; // a global variable
new bool:IsHeartEventWinner[MAX_PLAYERS]; // a global array.

CMD:somevent(playerid,params[]) // you mentioned it should be like an event.
{
     if(IsPlayerAdmin(playerid)) // you probably don't want to let anyone create these events
     {
           SendClientMessageToAll(0xFF0000FF,"Some event has been started");
           HeartPickup = CreatePickup(1240, 1, x,y,z,-1); // change x,y,z to your positions
           IsHeartEventWinner[SelectRandomPlayer()] = true;
     }
     return 1;
} 

public OnPlayerPickUpPickup(playerid,pickupid)
{
    if(pickupid == HeartPickup) // If its the heart pickup, not some other.
    {
            if(IsHeartEventWinner[playerid] == false) 
            {
                   SendClientMessage(playerid,0xFF0000FF,"BAD");
            }
            else 
            {
                   SendClientMessage(playerid,0x00FF00FF,"Good");
                   DestroyPickup(HeartPickup);
             }
    }
}

stock SelectRandomPlayer() // I found this function in forums.
{
     new random = Random(MAX_PLAYERS);
     if(IsPlayerConnected(random))
     {
           return random;
     }
     else
     {
           SelectRandomPlayer();
     }
}

new HeartsCollected[MAX_PLAYERS], HeartPickups[3];

public OnGameModeInit()
{
   HeartPickups[0] = CreatePickup(.... first heart);
   HeartPickups[1] = CreatePickup(.... second heart);
   HeartPickups[2] = CreatePickup(... third heart);
}

public OnPlayerPickUpPickup(playerid,pickupid)
{
    if(HeartPickups[0] == pickupid)
    {
          SendClientMessage(playerid, 0xFF0000FF, "You collected the first  heart!"); 
          HeartsCollected[playerid] = 1;
          return 1;
    }
    if(HeartPickups[1] == pickupid)
    {
         SendClientMessage(playerid,0xFF0000FF,"You collected the second heart. Only one left...");
         HeartsCollected[playerid] = 2;
         return 1;
    }
    if(HeartPickups[2] == pickupid)
    {
           SendClientMessage(playerid,0x00FF00FF,"It's the third heart. You get something!");
           HeartsCollected[playerid] = 0; // Let's asign 0. Maybe you'll let him to do it again..
           // You should also set it to 0 when a player disconnects.
           return 1;
    }
    return 0;
}