过度释放NSDecimalNumber

Question

我的应用程序告诉我，我过度发布了下面的NSDecimalNumber tempDouble：

NSNumberFormatter *currencyFormatter = [[NSNumberFormatter alloc] init];
        [currencyFormatter setLocale:[NSLocale currentLocale]];
        [currencyFormatter setGeneratesDecimalNumbers:TRUE];
        [currencyFormatter setNumberStyle:NSNumberFormatterCurrencyStyle];

        // Here is the key: use the maximum fractional digits of the currency as the scale
        int currencyScale = [currencyFormatter maximumFractionDigits];

        NSDecimalNumber* tempDouble = [[NSDecimalNumber alloc] initWithString:self.tempStore];


        NSDecimalNumber* numTen = [[NSDecimalNumber alloc] initWithInt:10];

        tempDouble = [tempDouble decimalNumberByDividingBy:[numTen decimalNumberByRaisingToPower:currencyScale]];

        [numTen release];


        [textField setText:[currencyFormatter stringFromNumber:tempDouble]];

        [currencyFormatter release];
        [tempDouble release];

我认为问题就是这一条：

tempDouble = [tempDouble decimalNumberByDividingBy:[numTen decimalNumberByRaisingToPower:currencyScale]];

但我不知道为什么。我应该在赋值后添加一个'assign，copy or retain‘属性吗？当我去掉下面的“release”语句时，代码运行得很好。

谢谢,

G

Answer 1

问题确实出在这一行：

tempDouble = [tempDouble decimalNumberByDividingBy:[numTen decimalNumberByRaisingToPower:currencyScale]];

您在这里所做的是将tempDouble中以前的值(保留计数为1)替换为一个新值(自动释放)。

下面是正确的方法：

NSDecimalNumber* tempDouble = [[[NSDecimalNumber alloc] initWithString:self.tempStore] autorelease];

然后从方法的末尾删除[tempDouble release]。