public OnPlayerEnterVehicle(playerid, vehicleid... etc)
{
  for(new b = 0; b < sizeof(DVehicles); b++)
  {
    new pname[24], string[256];
    GetPlayerName(playerid, pname, 24);
    format(string,sizeof(string),"{FFFFFF}This vehicle belongs to %s", DVehicles[b][Owner]);
    SendClientMessage(playerid, -1, string);
  }


    return 1;
}

enum vfInfo
{
    dID,
    dModel,   
    Float:dX,
    Float:dY,
    Float:dZ,
    Float:dA,
    dColor1,
    dColor2,
    Owner[24],
};

enum vfInfo
{
    dID,
    dModel,   
    Float:dX,
    Float:dY,
    Float:dZ,
    Float:dA,
    dColor1,
    dColor2,
    Owner[24],
};
new DVehicles[MAX_VEHICLES][vfInfo];//*******

public OnPlayerEnterVehicle(playerid, vehicleid... etc)
{
    new pname[24];
    GetPlayerName(playerid, pname, 24);
    if( DVehicles[vehicleid][Owner][0] && strcmp(name,DVehicles[vehicleid][Owner]) ) // if vehicle is not yours
    {
        new string[60];
        format(string,sizeof(string),"{FFFFFF}This vehicle belongs to %s", DVehicles[vehicleid][Owner]);
        SendClientMessage(playerid, -1, string);
        return 1;
    }
    return 1;
}