问数字与AS3中的数字不同

EN

function castBurn()
{
    var cardNumber = currentCard;// == 149 (currentCard:int)
    var card1 = cardNumber - 1;// 149 - 1 = 148
    var card2 = cardNumber + 1;// 149 +1 = 150
    var card3 = cardNumber - row;// row = 23 and so on
    var card4 = cardNumber + row;

    //cardArray:Array (full of objects(Cards)
    cardArray[card1].burn = true;// card1 is recognized and flips
    cardArray[card2].burn = true;// throws a runtime error (term is unidentified)
    cardArray[card3].burn = true;// See bottom for notes
    cardArray[card4].burn = true;

    for (var j = 0; j < cardArray.length; j++)
    {// This works 
        var card = cardArray[j];
        if (card.burn == true)
        {
            if (card.wall != true)
            {
                card.flip.gotoAndPlay(2);
            }
        }
    }
}