ios - 从 Objective-C 中的字符串获取日期

Question

我必须从字符串中获取日期，此处字符串的格式为“Monday 02,Dec 2013”​​，我必须将其转换为“2013-12-2”。我使用了以下代码，但我得到了错误的输出:

-(void)dateSelectedInPickerView:(NSString *)dateSelected{

    NSDateFormatter *dateFormatterForGettingDate = [[NSDateFormatter alloc] init];
    [dateFormatterForGettingDate setDateFormat:@"YYYY-MM-dd HH:mm:ss"];

    // Parse the string representation of the date i.e Monday 2,Dec 2013

    NSDate *dateFromStr = [dateFormatter dateFromString:dateSelected];
    NSLog(@"date selected  : %@",dateFromStr);

    NSDateFormatter *tempFormatter=[[NSDateFormatter alloc]init];
    [tempFormatter setDateFormat:@"YYYY-MM-dd"];

    self.reservationDateSelected=[tempFormatter stringFromDate:dateFromStr];
    NSLog(@"date Selected : %@",self.reservationDateSelected);
}

Answer 1

试试这个，它适用于 Monday 02,Dec 2013:

-(void)dateSelectedInPickerView:(NSString *)dateSelected{

NSDateFormatter *dateFormatterForGettingDate = [[NSDateFormatter alloc] init];
[dateFormatterForGettingDate setDateFormat:@"EEEE dd,MMM yyyy"];
[dateFormatterForGettingDate setLocale:[NSLocale localeWithLocaleIdentifier:@"EN"]];

// Parse the string representation of the date i.e Monday 2,Dec 2013

NSDate *dateFromStr = [dateFormatterForGettingDate dateFromString:dateSelected];
NSLog(@"date selected  : %@", [dateFromStr descriptionWithLocale:[NSLocale currentLocale]]);
NSDateFormatter *tempFormatter=[[NSDateFormatter alloc]init];
[tempFormatter setDateFormat:@"yyyy-MM-dd"];

self.reservationDateSelected=[tempFormatter stringFromDate:dateFromStr];
NSLog(@"date Selected : %@",self.reservationDateSelected);

}

Read this, if want to know more about Date Format Patterns ;-)