NSString和NSDate互相轉化

//目标格式：yyyy-MM-dd
    NSString *dateStr = @"2015-9-15";
    NSLog(@"initial dateStr:%@",dateStr);
    NSDateFormatter *inputFormatter = [[NSDateFormatter alloc] init];
    [inputFormatter setDateFormat:@"yyyy-MM-dd"];
    NSDate* inputDate = [inputFormatter dateFromString:dateStr];
    NSLog(@"inputDate:%@",inputDate);
    NSDateFormatter* outputFormatter = [[NSDateFormatter alloc] init];
    [outputFormatter setDateFormat:@"yyyy-MM-dd"];
    NSString *targetDateStr = [outputFormatter stringFromDate:inputDate];
    NSLog(@"targetDateStr:%@",targetDateStr);
           

輸出結果：

2015-11-26 09:03:26.615 TestStringDate[11220:685976] initial dateStr:2015-9-15

2015-11-26 09:03:26.618 TestStringDate[11220:685976] inputDate:2015-09-14 16:00:00 +0000

2015-11-26 09:03:26.619 TestStringDate[11220:685976] targetDateStr:2015-09-15