将NSDate转换为NSString

Question

如何转换,NSDate以NSString使得只有一年@"YYYY"格式输出到字符串？

Answer 1

怎么样...

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];

Swift 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

我不知道我们都错过了这个:localizedStringFromDate:dateStyle:timeStyle:

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

输出'13/06/12 00:22:39 GMT + 03:00'

Answer 3

希望通过提供包括年,月,日在内的常规格式化程序来增加更多价值.您可以使用此格式化程序超过一年

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

希望这有助于更多人

干杯Al

Answer 4

NSDate网上有很多帮手,我倾向于使用:

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

自述文件摘要如下:

  NSString *displayString = [NSDate stringForDisplayFromDate:date];

这会产生以下类型的输出:

‘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Swift中:

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NSDate -descriptionWithCalendarFormat:timeZone:locale:可用的（我不相信 iPhone/Cocoa Touch 包含这个），你可能需要使用 strftime 和 Monkey 以及一些 C 风格的字符串。NSDate您可以从using获取 UNIX 时间戳NSDate -timeIntervalSince1970。

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

只需添加这个扩展：

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