Question

我想将输入字符串转换为特定的NSDate格式，

这是我尝试过的代码。

NSString * result;
NSDate * resultDate;

NSDate *date = [dateFormat dateFromString:maxUpcomingDateString];
NSDateFormatter *dateFormat1 = [[NSDateFormatter alloc] init];

dateFormat1.locale=[[NSLocale alloc] initWithLocaleIdentifier:@"en_US"];
[dateFormat1 setDateFormat:@"yyyy/MMM/dd"];

NSLog(@"maxUpcomingDateString %@",maxUpcomingDateString)
NSDate *d=[dateFormat1 dateFromString:maxUpcomingDateString];

result = [dateFormat1 stringFromDate:date];
resultDate=[dateFormat1 dateFromString:result];

NSLog(@"max1 date upcoming %@",result);
NSLog(@"max2 date upcoming %@", resultDate);

我的日志输出显示：

maxUpcomingDateString 10 January 2017
max1 date upcoming 2017/Jan/10
max2 date upcoming (null)

我希望输出日期采用2017/Jan/10的形式。当我尝试记录字符串时，它会向我显示正确的输出，但当我将其转换回NSDate时，它显示为null。

Answer 1

nsstring to nsdate

NSString *dateString = @"01-02-2010";
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
// this is imporant - we set our input date format to match our input string
// if format doesn't match you'll get nil from your string, so be careful
[dateFormatter setDateFormat:@"dd-MM-yyyy"];
NSDate *dateFromString = [[NSDate alloc] init];

dateFromString = [dateFormatter dateFromString:dateString];

nsdate to nsstring

NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"dd-MM-yyyy"];
NSString *stringDate = [dateFormatter stringFromDate:[NSDate date]];
NSLog(@"%@", stringDate);

Answer 2

在dateFormat

上添加此代码

[dateFormat setDateFormat:@"dd MMM yyyy"];

它将解决问题。

Answer 3

在分配dateFormat对象后添加此代码。

NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];    
[dateFormat setDateFormat:@"dd MMM yyyy"];

无法将NSString转换为NSdate格式

3 个答案: