iOS：NumberFormatter，即使没有货币符号也会获得双倍值？

Question

在我的应用程序中，用户在一个视图中有多个输入字段用于货币值。因此，根据区域设置，字段中的值应显示为“$ 5.00”。这有效。

为了编辑字段，当用户输入值并删除货币符号时，我基本上“取消本地化”字符串。编辑后，应将值保存（当然也没有货币符号）到核心数据中。由于所有字段都需要以不同方式保存到数据库中，因此我必须遍历所有字段，并对所有核心数据值进行doverwrite。所以我必须“取消本地化”我视图的所有字段才能保存它们。这适用于除已编辑的文本字段之外的所有文本字段。如果我将这个已经非本地化的值发送到我的方法，它只返回0.为什么？

我的视图控制器的2种方法：

-(void)textFieldDidBeginEditing:(UITextField *)textField
{
    UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithTitle:NSLocalizedString(@"Done", nil) style:UIBarButtonItemStyleDone target:self action:@selector(doneEditing:)];
    [self.navigationBar setRightBarButtonItem:doneButton];

    if(textField.tag != 1){
        //1 is the name text field
        textField.text = [NSString stringWithFormat:@"%.2f",[NSNumber getUnLocalizedCurrencyDoubleWithString:textField.text]];
    }
}


    -(void)textFieldDidEndEditing:(UITextField *)textField
{
    self.spendingCategory.name = self.nameTextField.text;

    self.spendingCategory.costPerDay = [NSNumber numberWithDouble:[NSNumber getUnLocalizedCurrencyDoubleWithString:self.dailyTextField.text]];
    self.spendingCategory.costPerWeek = [NSNumber numberWithDouble:[NSNumber getUnLocalizedCurrencyDoubleWithString:self.weeklyTextField.text]];
    self.spendingCategory.costPerMonth = [NSNumber numberWithDouble:[NSNumber getUnLocalizedCurrencyDoubleWithString:self.monthlyTextField.text]];
    self.spendingCategory.costPerSemiYear = [NSNumber numberWithDouble:[NSNumber getUnLocalizedCurrencyDoubleWithString:self.semiAnnuallyTextField.text]];
    self.spendingCategory.costPerYear = [NSNumber numberWithDouble:[NSNumber getUnLocalizedCurrencyDoubleWithString:self.annuallyTextField.text]];

    [self setTextFieldsWithFormat];
}

我的NSNumber类别：

   - (NSString *) getLocalizedCurrencyString
{
    NSNumberFormatter *numberFormatter =[[NSNumberFormatter alloc] init];
    [numberFormatter setNumberStyle:NSNumberFormatterCurrencyStyle];

    NSString *numberString = [numberFormatter stringFromNumber:self];
    return numberString;
}

+ (double) getUnLocalizedCurrencyDoubleWithString:(NSString *)currencyString
{
    NSNumberFormatter *numberFormatter = [[NSNumberFormatter alloc] init];
    [numberFormatter setNumberStyle:NSNumberFormatterCurrencyStyle];

    return [[numberFormatter numberFromString:currencyString] doubleValue];
}

Answer 1

当textFieldDidEndEditing被调用在未定位的正在编辑的文本字段中的值时。我认为在取消本地化所有字符串之前，你缺少本地化编辑值的cal。在编辑的字符串上调用getUnlocalized将返回0，因为字符串不是货币样式。

因此你的didEndEditing应该是这样的 -

-(void)textFieldDidEndEditing:(UITextField *)textField
{
    self.spendingCategory.name = self.nameTextField.text;

    // First localize the current string that is being edited
    textField.text = [[NSNumber numberWithDouble:[textField.text doubleValue]] getLocalizedCurrencyString];

    // Now all of the strings are localized. Unlocalize and store them
    self.spendingCategory.costPerDay = [NSNumber numberWithDouble:[NSNumber getUnLocalizedCurrencyDoubleWithString:self.dailyTextField.text]];
    self.spendingCategory.costPerWeek = [NSNumber numberWithDouble:[NSNumber getUnLocalizedCurrencyDoubleWithString:self.weeklyTextField.text]];
   self.spendingCategory.costPerMonth = [NSNumber numberWithDouble:[NSNumber getUnLocalizedCurrencyDoubleWithString:self.monthlyTextField.text]];
self.spendingCategory.costPerSemiYear = [NSNumber numberWithDouble:[NSNumber getUnLocalizedCurrencyDoubleWithString:self.semiAnnuallyTextField.text]];
   self.spendingCategory.costPerYear = [NSNumber numberWithDouble:[NSNumber getUnLocalizedCurrencyDoubleWithString:self.annuallyTextField.text]];

  [self setTextFieldsWithFormat];
}