转换的NSDate到的NSString

Question

如何转换，NSDate到只有一年NSString所以在 @ “YYYY”格式输出字符串？

Answer 1

如何...

NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:@"yyyy"];

//Optionally for time zone conversions
[formatter setTimeZone:[NSTimeZone timeZoneWithName:@"..."]];

NSString *stringFromDate = [formatter stringFromDate:myNSDateInstance];

//unless ARC is active
[formatter release];

<强>夫特4.2：

func stringFromDate(_ date: Date) -> String {
    let formatter = DateFormatter()
    formatter.dateFormat = "dd MMM yyyy HH:mm" //yyyy
    return formatter.string(from: date)
}

Answer 2

我不知道我们怎么都错过了这个：的 localizedStringFromDate：DATESTYLE：timeStyle： 的

NSString *dateString = [NSDateFormatter localizedStringFromDate:[NSDate date] 
                                                      dateStyle:NSDateFormatterShortStyle 
                                                      timeStyle:NSDateFormatterFullStyle];
NSLog(@"%@",dateString);

输出'13 / 6月12日GMT〇时22分39秒+ 03：00'

Answer 3

希望通过提供正常的格式包括年，月，日与时间增添更多的价值。 您可以使用此格式的不仅仅是一年

[dateFormat setDateFormat: @"yyyy-MM-dd HH:mm:ss zzz"]; 

希望这有助于更多的人

干杯 人

Answer 4

有一些在网络上NSDate助手，我倾向于使用：

https://github.com/billymeltdown/nsdate-helper/

下面自述提取：

  NSString *displayString = [NSDate stringForDisplayFromDate:date];

这产生以下种输出：

‘3:42 AM’ – if the date is after midnight today
‘Tuesday’ – if the date is within the last seven days
‘Mar 1’ – if the date is within the current calendar year
‘Mar 1, 2008’ – else ;-)

Answer 5

在夫特：

var formatter = NSDateFormatter()
formatter.dateFormat = "yyyy"
var dateString = formatter.stringFromDate(YourNSDateInstanceHERE)

Answer 6

  NSDateFormatter *dateformate=[[NSDateFormatter alloc]init];
  [dateformate setDateFormat:@"yyyy"]; // Date formater
  NSString *date = [dateformate stringFromDate:[NSDate date]]; // Convert date to string
  NSLog(@"date :%@",date);

Answer 7

如果你没有可用NSDate -descriptionWithCalendarFormat:timeZone:locale:（我不相信iPhone /可可触摸包含这个），你可能需要一些C风格的字符串周围使用的strftime和猴子。您可以使用NSDate从NSDate -timeIntervalSince1970获得UNIX时间戳。

Answer 8

+(NSString*)date2str:(NSDate*)myNSDateInstance onlyDate:(BOOL)onlyDate{
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    if (onlyDate) {
        [formatter setDateFormat:@"yyyy-MM-dd"];
    }else{
        [formatter setDateFormat: @"yyyy-MM-dd HH:mm:ss"];
    }

    //Optionally for time zone conversions
    //   [formatter setTimeZone:[NSTimeZone timeZoneWithName:@"..."]];

    NSString *stringFromDate = [formatter stringFromDate:myNSDateInstance];
    return stringFromDate;
}

+(NSDate*)str2date:(NSString*)dateStr{
    if ([dateStr isKindOfClass:[NSDate class]]) {
        return (NSDate*)dateStr;
    }

    NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];
    [dateFormat setDateFormat:@"yyyy-MM-dd"];
    NSDate *date = [dateFormat dateFromString:dateStr];
    return date;
}

Answer 9

只需添加此扩展：

extension NSDate {
    var stringValue: String {
        let formatter = NSDateFormatter()
        formatter.dateFormat = "yourDateFormat"
        return formatter.stringFromDate(self)
    }
}

Answer 10

如果您在Mac OS X，你可以这样写：

NSString* s = [[NSDate date] descriptionWithCalendarFormat:@"%Y_%m_%d_%H_%M_%S" timeZone:nil locale:nil];

然而，这不适用于iOS。

Answer 11

NSCalendar *calendar = [NSCalendar currentCalendar];
NSDateComponents *components = [calendar components:(NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay) fromDate:myNSDateInstance];
NSInteger year = [components year];
// NSInteger month = [components month];
NSString *yearStr = [NSString stringWithFormat:@"%ld", year];

Answer 12

定义自己的效用格式的日期所需的日期格式 为例如

NSString * stringFromDate(NSDate *date)  
 {   NSDateFormatter *formatter
    [[NSDateFormatter alloc] init];  
    [formatter setDateFormat:@"MM ∕ dd ∕ yyyy, hh꞉mm a"];    
    return [formatter stringFromDate:date]; 
}

Answer 13

这是迅速格式：

func dateFormatterWithCalendar(calndarIdentifier: Calendar.Identifier, dateFormat: String) -> DateFormatter {

    let formatter = DateFormatter()
    formatter.calendar = Calendar(identifier: calndarIdentifier)
    formatter.dateFormat = dateFormat

    return formatter
}


//Usage
let date = Date()
let fotmatter = dateFormatterWithCalendar(calndarIdentifier: .gregorian, dateFormat: "yyyy")
let dateString = fotmatter.string(from: date)
print(dateString) //2018

Answer 14

迅速4答案

static let dateformat: String = "yyyy-MM-dd'T'HH:mm:ss"
public static func stringTodate(strDate : String) -> Date
{

    let dateFormatter = DateFormatter()
    dateFormatter.dateFormat = dateformat
    let date = dateFormatter.date(from: strDate)
    return date!
}
public static func dateToString(inputdate : Date) -> String
{

    let dateFormatter = DateFormatter()
    dateFormatter.dateFormat = dateformat
    return formatter.string(from: inputdate)

}