Question

我试图以可读格式显示2日期的差异。从下面的代码可以看出，有很多if-else闭包。是否有任何格式化程序或我的if-elses方式是对的？

NSCalendar *c = [NSCalendar currentCalendar];
NSDateComponents *components = [c components:(NSCalendarUnitMonth | NSCalendarUnitDay)
                                        fromDate:startDate
                                          toDate:endDate
                                         options:0];

NSString *leftTimeStr = @"";
if (components.month == 0) {
    if (components.day == 1) {
        leftTimeStr = @"after 1 day";
    }
    else if (components.day > 1) {
        leftTimeStr = [NSString stringWithFormat:@"after %ld days", (long)components.day];
    }
}
else if (components.month == 1) {
    if (components.day == 0) {
        leftTimeStr = @"after 1 month";
    }
    else if (components.day == 1) {
        leftTimeStr = @"after 1 month 1 day";
    }
    else if (components.day > 1) {
        leftTimeStr = [NSString stringWithFormat:@"after 1 month %ld days", (long)components.day];
    }
}
else if (components.month > 1) {
    if (components.day == 0) {
        leftTimeStr = [NSString stringWithFormat:@"after %ld months", (long)components.month];
    }
    else if (components.day == 1) {
        leftTimeStr = [NSString stringWithFormat:@"after %ld months 1 day", (long)components.month];
    }
    else if (components.day > 1) {
        leftTimeStr = [NSString stringWithFormat:@"after %ld months %ld days", (long)components.month, (long)components.day];
    }
}

结果leftTimeStr字符串应该像下面的字符之一：

"after 5 months 22 days",
"after 5 months 1 day",
"after 5 months",
"after 1 month 22 days",
...
"after 22 days",
"after 1 day"

Answer 1

使用以下类别NSDate。

NSDate *date = [[NSDate alloc] initWithTimeIntervalSince1970:0];
NSString *ago = [date timeAgo];
NSLog(@"Output is: \"%@\"", ago);
2011-11-12 17:19:25.608 Proj[0:0] Output is: "41 years ago"

Source from GitHub

Answer 2

为此，您可以使用NSDateComponentsFormatter。

NSDateComponentsFormatter *formatter = [[NSDateComponentsFormatter alloc] init];
[formatter setAllowedUnits:NSCalendarUnitMonth | NSCalendarUnitDay];
formatter.maximumUnitCount = 2;
formatter.unitsStyle = NSDateComponentsFormatterUnitsStyleFull;
NSString *difference = [formatter stringFromDate:startDate toDate:endDate];

Answer 3

您可以NSDateComponentsFormatter使用SpellOut单位样式，可以输出如下内容：＆＃34;一小时十分钟＆＃34;。

点击此处查看详细信息：http://nshipster.com/nsformatter/#nsdatecomponentsformatter

iOS可读字符串/日期格式化程序

3 个答案: