Question

我尝试将NSString转换为NSDate对象，但NSDateFormatter会给我一个奇怪的值。我想要01/07/2016，但它会返回错误的输出。输出是：

今天：2015-12-20 00:00:00 +0000

这是代码：

NSDateComponents *components = [[NSCalendar currentCalendar] components:NSCalendarUnitDay | NSCalendarUnitMonth | NSCalendarUnitYear fromDate:[NSDate date]];

NSInteger day = 01;
NSInteger week = 07;
NSInteger year = [components year];

NSString *string = [NSString stringWithFormat:@"%ld/%ld/%ld",  (long)week,(long)day, (long)year];
NSLog(@"Min Date: %@",string);

NSDateFormatter *dateformate=[[NSDateFormatter alloc]init];
[dateformate setTimeZone:[NSTimeZone timeZoneWithName:@"UTC"]];
[dateformate setDateFormat:@"MM/dd/YY"];

strMinDate = [dateformate dateFromString:string];
NSLog(@"Today: %@", strMinDate);

Answer 1

这里需要清理很多事情。

将您的week变量重命名为month。
您的日期格式错误。它应该是@"MM/dd/yyyy。
不要使用八进制数字。

这应该按照书面形式修复你的代码。

但是，没有理由让NSDateFormatter参与其中。只需直接从更新的NSDateComponents创建新日期。

NSDateComponents *components = [[NSCalendar currentCalendar] components:NSCalendarUnitDay | NSCalendarUnitMonth | NSCalendarUnitYear fromDate:[NSDate date]];

components.day = 1;
components.month = 7; // July

NSDate *minDate = [NSCalendar dateFromComponents:components];

这将以当地时间为您提供新的日期。

如果您拥有正确的NSDate，现在可以使用NSDateFormatter将其格式化为您选择的字符串。

NSDateFormatter *dateformat = [[NSDateFormatter alloc] init];
[dateformat setDateFormat:@"dd/MM/yy"];
NSString *dayMonthYearStr = [dateFormat stringFromDate:minDate];

Answer 2

您可以尝试以下代码：

NSDateComponents *components = [[NSCalendar currentCalendar] components:NSCalendarUnitDay | NSCalendarUnitMonth | NSCalendarUnitYear fromDate:[NSDate date]];

NSInteger day = 01;
NSInteger month = 07;
NSInteger year = [components year];

NSString *string = [NSString stringWithFormat:@"%ld/%ld/%ld",  (long)year,(long)month, (long)day];

NSLog(@"Min Date: %@",string);
NSString *date_str = string;
NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];
[dateFormat setDateFormat:@"yyyy/MM/dd"];
NSTimeZone *gmt = [NSTimeZone timeZoneWithName:@"GMT"];
[dateFormat setTimeZone:gmt];
NSDate *date = [dateFormat dateFromString:date_str];
NSLog(@"%@",date);

将NSString转换为NSDate的输出错误

2 个答案: