dateFromString 返回 nil

Question

我有一个将 NSString 转换为 NSDate 的函数。

+ (NSDate *)getNSDateFromString:(NSString *)strDate andFormat:(NSString *)format{
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    [formatter setDateFormat : format];
    NSString *stringTime = strDate;
    NSDate *dateTime = [formatter dateFromString:stringTime];
    return dateTime;
}

strDate 的值为“2018 年 3 月 27 日 18:28:09”。格式为 "dd-MM-yyyy HH:mm:ss"

该函数正在返回 nil 值。任何人都可以帮忙吗？谢谢

Answer 1

将日期格式更改为 dd-MMM-yyyy HH:mm:ss

这里有很好的参考资料来理解日期格式字符串：Quick Guide to Objective-C DateFormatting & Date_Field_Symbol_Table

y = year
Q = quarter
M = month
w = week of year
W = week of month
d = day of the month
D = day of year
E = day of week
a = period (AM or PM)
h = hour (1-12)
H = hour (0-23)
m = minute
s = second

如果您将此与您的日期组件相匹配

27-Mar-2018 18:28:09 = dd-MMM-yyyy HH:mm:ss

在哪里

27   = dd (date day)
Mar  = MMM (Month)
2018 = yyyy (year)
18   = HH (HH - 24 hours format and hh - 12 hours format)
28   = mm (minutes)
09   = ss (seconds)

Answer 2

因为您的日期字符串是“27-Mar-2018 18:28:09”。格式应为 "dd-MMM-yyyy HH:mm:ss".

将格式从 "dd-MM-yyyy HH:mm:ss" 更改为 "dd-MMM-yyyy HH:mm:ss"

dateFromString 返回 nil

dateFromString returning nil

objective-c

nsdateformatter

ios