ios datePicker简单写法
头文件里定义 label 和 datepicker

@interface ViewController : UIViewController{    UILabel *dateLabel;    UIDatePicker *datePicker;}@property (nonatomic,retain)IBOutlet UILabel *dateLabel;@property(nonatomic,retain)IBOutlet UIDatePicker *datePicker;-(IBAction)dateChanged:(id)sender;@end

@synthesize dateLabel;@synthesize datePicker;- (void)viewDidLoad{    [super viewDidLoad];    NSDate *date = [NSDate date];    [datePicker setDate:date animated:YES];    

-(IBAction)dateChanged:(id)sender{    NSDate *curDate =[datePicker date];    NSDateFormatter *formate = [[NSDateFormatter alloc] init];    [formate setDateStyle:NSDateFormatterLongStyle];    [formate setTimeStyle:NSDateFormatterLongStyle];        NSString *formateDateString = [formate stringFromDate:curDate];    NSLog(@"string is %@" ,formateDateString);    dateLabel.text = [NSString stringWithFormat:                      @"当前时间是 %@", formateDateString];//    [formate release];}

   [super viewDidLoad];    NSDate *date = [NSDate date];    [datePicker setDate:date animated:YES];    NSCalendar *cul =[NSCalendar currentCalendar];    NSDateComponents *com = [cul components:NSYearCalendarUnit|                                   NSMonthCalendarUnit|                             NSDayCalendarUnit|                             NSHourCalendarUnit|                             NSMinuteCalendarUnit|                             NSSecondCalendarUnit                                   fromDate:date];    NSLog(@"time is %d-%d-%d %02d:%02d:%02d",          [com year],          [com month],          [com day],          [com hour],          [com minute],          [com second]);        NSDateFormatter *formater =[[NSDateFormatter alloc]init];    [formater setDateFormat:@"YYYY-MM-DD"];    NSString *dl = [formater stringFromDate:date];    NSLog(@"CURRENT TIME %@",dl);