NSDateFormatter 谜题！这是新的山狮虫吗？

我相信我可能发现了一个错误NSDateFormatter，我不确定这是否本地化为在系统偏好设置中指定了巴西时区。

完整的项目在这里：http://www.idanfe.com/dl/nsDateFormatterPuzzle.zip http://www.idanfe.com/dl/nsDateFormatterPuzzle.zip

相关代码摘录如下所示：

NSArray *unformattedDatesArray = [[NSArray alloc] initWithObjects:@"2011-09-18",
     @"2011-10-16",@"2011-11-13",@"2011-12-11",@"2012-01-08",@"2012-02-05", nil];

NSString *resultedString = @"";
int ii = 0;
NSUInteger items = [unformattedDatesArray count];
for (ii=0; ii<items; ii++) {
    NSLog(@"original item # %d = %@",ii,[unformattedDatesArray objectAtIndex:ii]);
    resultedString = [resultedString stringByAppendingString:@"original item # "];
    resultedString = [resultedString stringByAppendingString:[NSString stringWithFormat: @"%d = ",ii]];
    resultedString = [resultedString stringByAppendingString:[unformattedDatesArray objectAtIndex:ii]];
    resultedString = [resultedString stringByAppendingString:[NSString stringWithFormat:@"\n"]];
}
NSDateFormatter *originalFormat = [[NSDateFormatter alloc] init];
[originalFormat setDateFormat:@"yyyy-MM-dd"]; // hh:mm:ss
NSDateFormatter *newFormat = [[NSDateFormatter alloc] init];
[newFormat setDateFormat:@"dd/MM/yyyy"]; // hh:mm:ss
NSString *formattedDate;
for (ii=0; ii<items; ii++) {
    formattedDate = [newFormat stringFromDate:[originalFormat
                                               dateFromString:[unformattedDatesArray objectAtIndex:ii]]];
    NSLog(@"formatted item # %d = %@",ii,formattedDate);
    resultedString = [resultedString stringByAppendingString:@"formatted item # "];
    resultedString = [resultedString stringByAppendingString:[NSString stringWithFormat: @"%d = ",ii]];
    resultedString = [resultedString stringByAppendingString:(formattedDate == nil ? @"ERROR" : formattedDate)];
    resultedString = [resultedString stringByAppendingString:[NSString stringWithFormat:@"\n"]];
}
[resultingStringTextView insertText:resultedString];

基本上，我从 5 个数组开始NSStrings 代表日期。我正在创建 2NSDateFormatters: originalFormat用于将日期的原始字符串表示形式转换为实际的日期NSDate; newFormat用于创建新的所需字符串表示形式NSDate生成的originalFormat日期格式化程序。

这是我生成的日志：

2012-08-26 nsDateFormatterPuzzle[3261:303] original item # 0 = 2011-09-18
2012-08-26 nsDateFormatterPuzzle[3261:303] original item # 1 = 2011-10-16
2012-08-26 nsDateFormatterPuzzle[3261:303] original item # 2 = 2011-11-13
2012-08-26 nsDateFormatterPuzzle[3261:303] original item # 3 = 2011-12-11
2012-08-26 nsDateFormatterPuzzle[3261:303] original item # 4 = 2012-01-08
2012-08-26 nsDateFormatterPuzzle[3261:303] original item # 5 = 2012-02-05
2012-08-26 nsDateFormatterPuzzle[3261:303] formatted item # 0 = 18/09/2011
2012-08-26 nsDateFormatterPuzzle[3261:303] formatted item # 1 = (null)
2012-08-26 nsDateFormatterPuzzle[3261:303] formatted item # 2 = 13/11/2011
2012-08-26 nsDateFormatterPuzzle[3261:303] formatted item # 3 = 11/12/2011
2012-08-26 nsDateFormatterPuzzle[3261:303] formatted item # 4 = 08/01/2012
2012-08-26 nsDateFormatterPuzzle[3261:303] formatted item # 5 = 05/02/2012

请注意，如果您转到系统偏好设置 --> 日期和时间 --> 时区

并将您的时区更改为里约热内卢，您将得到相同的结果。

================================== 尝试解决方法============== ===================

我正在尝试解决这个错误，而苹果却没有修复它。

我有两个问题，一个是从该日期开始渲染 PDF 文件，我想我已经通过以下方式解决了这个问题：

 if (formated_issue_date == NULL) {
            formated_issue_date = [BHDateFormatter bhDateFormat:data_emissao];

}

使用此处理程序：

+(NSString*)bhDateFormat:(NSString *)inputedDate{

    NSString *formattedDate = @"";

    NSRange range82 = NSMakeRange (8, 2);
    NSRange range52 = NSMakeRange (5, 2);
    NSRange range04 = NSMakeRange (0, 4);

    NSString *firstBlock = [inputedDate substringWithRange:range82];
    NSString *secondBlock = [inputedDate substringWithRange:range52];
    NSString *thirdBlock = [inputedDate substringWithRange:range04];

    formattedDate = [formattedDate stringByAppendingString:firstBlock];
    formattedDate = [formattedDate stringByAppendingString:@"/"];
    formattedDate = [formattedDate stringByAppendingString:secondBlock];
    formattedDate = [formattedDate stringByAppendingString:@"/"];
    formattedDate = [formattedDate stringByAppendingString:thirdBlock];

    return formattedDate;
}

第二个问题是发票日期被加载到包含日期格式化程序的表视图中，更改它会导致表的排序丢失。

使用与我的处理程序相同的原则，并坚持传递 16/10/2011 日期会导致表视图上出现错误，例如： -[__NSCFString timeIntervalSinceReferenceDate]: 无法识别的选择器发送到实例 0x40265f3a0

这是迄今为止我发现的最好的代码：

if (formatterDate == NULL) {
                        NSLog (@"outprintString '%@' = NULL", dateString);
                        NSString *newDate = [BHDateFormatter bhDateFormat:dateString];
                        if ([newDate isEqualToString:@"16/10/2011"]) {
                            formatterDate = [inputFormatter dateFromString:@"2011-10-17"];
                            NSLog(@"formatterDate = %@", formatterDate);
                            NSAlert *alert = [[[NSAlert alloc]init] autorelease];
                            [alert setMessageText:[NSString stringWithFormat:NSLocalizedString(@"Mountain Lion Bug: I have found a date \"16/10/2011\" in your invoice # %@ issued by %@, I must rename the date in your table view to \"17/10/2011\", the date on the rendered invoice file will be display correctly. I apologize for this, but it is an operating system level bug that has to be fixed by Apple.","A comment here"),invoiceNumber, emitente]];
                            [alert runModal];
                        }
                    }

您能评论一下吗？

Thanks!

我相信你是对的——这是一个错误，你应该报告它。有趣的是，如果您将时区设置为努克-格陵兰岛，它与里约热内卢位于同一时区，则它可以正常工作。另外，“2011-10-15”和“2011-10-17”适用于里约时区，但不适用于“2011-10-16”，这真的很奇怪。

这是我用来测试的简化代码：

- (void)applicationDidFinishLaunching:(NSNotification *)aNotification {

    NSArray *unformattedDatesArray = [[NSArray alloc] initWithObjects:@"2011-09-18",@"2011-10-16",@"2011-11-13",@"2011-12-11",@"2012-01-08",@"2012-02-05", nil];

    NSDateFormatter *originalFormat = [[NSDateFormatter alloc] init];
    [originalFormat setDateFormat:@"yyyy-MM-dd"]; // hh:mm:ss
    NSDateFormatter *newFormat = [[NSDateFormatter alloc] init];
    [newFormat setDateFormat:@"dd/MM/yyyy"]; // hh:mm:ss

    for (NSString * aString in unformattedDatesArray) {
        NSString *formattedDate = [newFormat stringFromDate:[originalFormat dateFromString:aString]];
        NSLog(@"Original date string is: %@  formatted date as string is: %@",aString, formattedDate);
    }
}

补充信息：

为了找到这个问题的根源，我使用以下代码循环遍历了 2011 年的所有日期：

- (void)applicationDidFinishLaunching:(NSNotification *)aNotification {

    NSDateFormatter *originalFormat = [[NSDateFormatter alloc] init];
    [originalFormat setDateFormat:@"yyyy-MM-dd"]; // hh:mm:ss
    NSDateFormatter *newFormat = [[NSDateFormatter alloc] init];
    [newFormat setDateFormat:@"dd/MM/yyyy"]; // hh:mm:ss

    NSDate *start = [originalFormat dateFromString:@"2011-01-01"];
    NSDate *newDate;
    for (int i=0; i<365; i++) {
        newDate = [start dateByAddingTimeInterval:86400 * i];
        NSString *formattedDate = [newFormat stringFromDate:newDate];
        NSLog(@"formatted date as string is: %@",formattedDate);
    }
}

当您查看日期字符串时，您会发现有 2 月 19 日，没有 10 月 16 日，这就是为什么该日期为 null（尽管如果您记录日期对象本身，则可以正确获取所有日期）。