如何在iPhone中以AM / PM格式打印时间？

Question

我想从日期选择器中打印时间，但要带有AM / PM。我可以打印时间，但从不打印AM / PM。我该怎么办？

Answer 1

您可以使用此文档以获取更多信息NSDateFormatter Class Reference一个例子可能是：

NSDate* date = [NSDate date];
NSDateFormatter* dateFormatter = [[[NSDateFormatter alloc] init] autorelease];
[dateFormatter setDateFormat:@"MM/dd/yyyy"];

[formatter setTimeStyle:NSDateFormatterFullStyle];
NSLog(@"date=%@",[dateFormatter stringFromDate:date]);

Answer 2

在下面的代码行中使用

    NSDateFormatter *dateFormatter = [[[NSDateFormatter alloc] init] autorelease];
    [dateFormatter setDateFormat:@"hh:mm a"];   
    NSString *str_date = [dateFormatter stringFromDate:[NSDate date]];
    NSLog(@"str_date:%@",str_date);

Answer 3

您可以如下设置DateFormatter amSymbol和pmSymbol：

Xcode 8.3•Swift 3.1

let formatter = DateFormatter()
formatter.dateFormat = "h:mm a 'on' MMMM dd, yyyy"
formatter.amSymbol = "AM"
formatter.pmSymbol = "PM"

let dateString = formatter.string(from: Date())
print(dateString)   // "4:44 PM on June 23, 2016\n"

编辑：目标C代码

NSDateFormatter *df = [[NSDateFormatter alloc] init];
df.timeZone = [NSTimeZone systemTimeZone];
df.AMSymbol = @"AM";
df.PMSymbol = @"PM";
df.dateFormat = "h:mm a 'on' MMMM dd, yyyy"
NSString *stringDate = [df stringFromDate:dateFromString];

引用链接：https://stackoverflow.com/a/31469237/2905967

Answer 4

日期到字符串

NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:@“dd-MMM”];
cell.dateLabel.text = [formatter stringFromDate:item.pubDate]

日期格式符号Unicode日期格式页面上的表应该足以让您构建自己所需的日期格式字符串…

Pattern Result (in a particular locale)
yyyy.MM.dd G ‘at’ HH:mm:ss zzz  1996.07.10 AD at 15:08:56 PDT
EEE, MMM d, ‘’yy    Wed, July 10, ‘96
h:mm a  12:08 PM
hh ‘o’‘clock’ a, zzzz   12 o’clock PM, Pacific Daylight Time
K:mm a, z   0:00 PM, PST
yyyyy.MMMM.dd GGG hh:mm aaa 01996.July.10 AD 12:08 PM
Hope this is useful to someone out there.

使用以下链接获取更多数据。

http://benscheirman.com/2010/06/dealing-with-dates-time-zones-in-objective-c/

这确实帮助了我。真的很简单。

Answer 5

对于打印AM / PM，参数a/aa/aaa全部将起作用。

NSDateFormatter *myDateFormatter = [[[NSDateFormatter alloc] init] autorelease];
[myDateFormatter setDateFormat:@"hh:mm aaa"]; //a,aa or aa all will work.
[myDateFormatter setDateFormat:@"hh:mm aa"];
NSString *myDate = [myDateFormatter stringFromDate:[NSDate date]];
NSLog(@"myDate is :%@",myDate);

Answer 6

您可以快速使用5

    var strDate1:String = "2019-12-19 05:42:04";
    let dateFormatter = DateFormatter()
    dateFormatter.dateFormat = "yyyy-MM-dd HH:mm:ss"
    let dateObj = dateFormatter.date(from: strDate1)
    dateFormatter.dateFormat = "yyyy-MM-dd HH:mm:ss a"
    let strigDate =  dateFormatter.string(from: dateObj!)

输出：2019-12-19 05:42:04 AM