iOS 获取当前时间并且显示走在视图上

//

//  RootViewController.m

//  时间戳在走并且显示Demo

//

//  Created by Dubai on 15/4/2.

//  Copyright (c) 2015年 Dubai. All rights reserved.

//

#import "RootViewController.h"

@interface RootViewController ()

{

    UILabel *labelTime;

    NSTimer *timeNow;

}

@end

@implementation RootViewController

- (void)viewDidLoad {

    [super viewDidLoad];

    // Do any additional setup after loading the view.

    self.view.backgroundColor = [UIColor orangeColor];

    labelTime = [[UILabel alloc] initWithFrame:CGRectMake(60, 100, 200, 50)];

    labelTime.backgroundColor = [UIColor redColor];

    [self.view addSubview:labelTime];

    timeNow = [NSTimer scheduledTimerWithTimeInterval:1.0f target:self selector:@selector(timerFunc) userInfo:nil repeats:YES];

    //获取系统时间

    NSDate *  senddate=[NSDate date];

    NSDateFormatter  *dateformatter=[[NSDateFormatter alloc] init];

    [dateformatter setDateFormat:@"HH:mm"];

    NSString *  locationString=[dateformatter stringFromDate:senddate];

    NSLog(@"-------%@",locationString);

    //获取系统时间

    NSCalendar  * cal=[NSCalendar  currentCalendar];

    NSUInteger  unitFlags=NSDayCalendarUnit|NSMonthCalendarUnit|NSYearCalendarUnit;

    NSDateComponents * conponent= [cal components:unitFlags fromDate:senddate];

    NSInteger year=[conponent year];

    NSInteger month=[conponent month];

    NSInteger day=[conponent day];

    NSString *  nsDateString= [NSString  stringWithFormat:@"%4d年%2d月%2d日",year,month,day];

    NSLog(@"+++++++++++++%@",nsDateString);

}

- (void)timerFunc

{

    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];

    [formatter setDateFormat:@"MM/dd/YY HH:mm:ss"];

    NSString *timestamp = [formatter stringFromDate:[NSDate date]];

    [labelTime setText:timestamp];//时间在变化的语句

    NSLog(@"%@",timestamp);

}

- (void)didReceiveMemoryWarning {

    [super didReceiveMemoryWarning];

    // Dispose of any resources that can be recreated.

}

/*

#pragma mark - Navigation

// In a storyboard-based application, you will often want to do a little preparation before navigation

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {

    // Get the new view controller using [segue destinationViewController].

    // Pass the selected object to the new view controller.

}

*/

@end