如何在 iOS 中将日期字符串解析为 NSDate 对象? [英] How to parse a date string into an NSDate object in iOS?

问题描述

我正在尝试将 xml 中的日期字符串解析为 iPhone 应用程序中的 NSDate 对象

I am trying to parse a date string from xml into an NSDate object in an iPhone app

我知道之前一定有人问过这个问题，但是，我相信我有正确的语法，但它不起作用.我的代码有问题吗?

I am aware this must have been asked before, however, I believe I have the right syntax, but it is not working. Is there a problem with my code?

我需要解析的日期字符串是:

The date string I need to parse is:

2011-01-21T12:26:47-05:00

我用来解析它的代码是:

The code I am using to parse it is:

self.dateFormatter = [[NSDateFormatter alloc] init];
    [self.dateFormatter setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:0]];
    [self.dateFormatter setLocale:[[[NSLocale alloc] initWithLocaleIdentifier:@"en_US_POSIX"] autorelease]];
    [self.dateFormatter setDateFormat:@"yyyy'-'MM'-'dd'T'HH':'mm':'ss'Z'"];



... 

else if([elementName isEqualToString:kUpdated]){
    self.currentQuestion.updated = [self.dateFormatter dateFromString:self.currentParsedCharacterData ];
}

非常感谢任何帮助.谢谢！

Any help greatly appreciated. Thanks!

**基于来自 theChrisKent 的链接引用，我解决了这样的问题:

**Based on the link reference from theChrisKent I fixed the problem like so:

else if([elementName isEqualToString:kLastOnDeck]){

    NSString *dateStr = self.currentParsedCharacterData;
    // we need to strip out the single colon
    dateStr = [dateStr stringByReplacingOccurrencesOfString:@":" 
                                                 withString:@"" 
                                                    options:0 
                                                      range:NSMakeRange([dateStr length] - 5,5)];




    self.currentQuestion.lastOnDeck = [dateFormatter dateFromString:dateStr];

}

推荐答案

你不需要尽可能多的单引号(只需要非日期/时间字符)，所以改变这个:

You don't need near as many single quotes as you have (only needed on non date/time characters), so change this:

[self.dateFormatter setDateFormat:@"yyyy'-'MM'-'dd'T'HH':'mm':'ss'Z'"];

为此:

[self.dateFormatter setDateFormat:@"yyyy-MM-dd'T'HH:mm:ssZZZ"];
...
self.currentQuestion.updated = [self.dateFormatter dateFromString:[self.currentParsedCharacterData stringByReplacingOccurrencesOfString:@":" withString:@"" options:0 range:NSMakeRange([self.currentParsedCharacterData length] – 5,5)]];

<小时>

此处的文档:https://developer.apple.com/library/content/documentation/Cocoa/Conceptual/DataFormatting/Articles/dfDateFormatting10_4.html#//apple_ref/doc/uid/TP40002369-SW1

Unicode 格式模式:http://unicode.org/reports/tr35/tr35-6.html#Date_Format_Patterns

Unicode Format Patterns: http://unicode.org/reports/tr35/tr35-6.html#Date_Format_Patterns

处理带冒号的时区 (+00:00):http://petersteinberger.com/2010/05/nsdateformatter-and-0000-parsing/

Dealing with TimeZones with Colons (+00:00): http://petersteinberger.com/2010/05/nsdateformatter-and-0000-parsing/

这篇关于如何在 iOS 中将日期字符串解析为 NSDate 对象?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！