iOS实现秒杀活动倒计时

ios关于大型网站抢购、距活动结束，剩余时间倒计时的实现代码，代码比较简单，大家根据需求适当的添加修改删除代码

1.定义4个 label 来接收倒计时:

@property (weak, nonatomic) iboutlet uilabel *daylabel;
@property (weak, nonatomic) iboutlet uilabel *hourlabel;
@property (weak, nonatomic) iboutlet uilabel *minutelabel;
@property (weak, nonatomic) iboutlet uilabel *secondlabel;

2.在实现文件中实现方法:

//时间戳转换为日期格式(毫秒的时间戳)
- (nsstring *)timewithtimeintervalstring:(nsstring *)timestring
{
  // 格式化时间
  nsdateformatter* formatter = [[nsdateformatter alloc] init];
  formatter.timezone = [nstimezone timezonewithname:@"shanghai"];
  [formatter setdatestyle:nsdateformattermediumstyle];
  [formatter settimestyle:nsdateformattershortstyle];
  [formatter setdateformat:@"yyyy-mm-dd hh:mm:ss"];

  // 毫秒值转化为秒
  nsdate* date = [nsdate datewithtimeintervalsince1970:[timestring doublevalue]/ 1000.0];
  nsstring* datestring = [formatter stringfromdate:date];
  nslog(@"时间 === %@",datestring);
  return datestring;
}
-(void)downsecondhandle:(nsstring *)atimestring{

  nsdateformatter *dateformatter=[[nsdateformatter alloc] init];
  [dateformatter setdateformat:@"yyyy-mm-dd hh:mm:ss"];


  nsdate *enddate = [dateformatter datefromstring:[self timewithtimeintervalstring:atimestring]]; //结束时间
  nsdate *enddate_tomorrow = [[nsdate alloc] initwithtimeintervalsincereferencedate:([enddate timeintervalsincereferencedate])];
  nsdate *startdate = [nsdate date];
    nsstring* datestring = [dateformatter stringfromdate:startdate];
  nslog(@"现在的时间 === %@",datestring);
  nstimeinterval timeinterval =[enddate_tomorrow timeintervalsincedate:startdate];

  if (_timer==nil) {
    __block int timeout = timeinterval; //倒计时时间

    if (timeout!=0) {
      dispatch_queue_t queue = dispatch_get_global_queue(dispatch_queue_priority_default, 0);
      _timer = dispatch_source_create(dispatch_source_type_timer, 0, 0,queue);
      dispatch_source_set_timer(_timer,dispatch_walltime(null, 0),1.0*nsec_per_sec, 0); //每秒执行
      dispatch_source_set_event_handler(_timer, ^{
        if(timeout<=0){ //倒计时结束，关闭
          dispatch_source_cancel(_timer);
          _timer = nil;
          dispatch_async(dispatch_get_main_queue(), ^{
            self.daylabel.text = @"";
            self.hourlabel.text = @"00";
            self.minutelabel.text = @"00";
            self.secondlabel.text = @"00";
          });
        }else{
          int days = (int)(timeout/(3600*24));
          if (days==0) {
            self.daylabel.text = @"";
          }
          int hours = (int)((timeout-days*24*3600)/3600);
          int minute = (int)(timeout-days*24*3600-hours*3600)/60;
          int second = timeout-days*24*3600-hours*3600-minute*60;
          dispatch_async(dispatch_get_main_queue(), ^{
            if (days==0) {
              self.daylabel.text = @"0天";
            }else{
              self.daylabel.text = [nsstring stringwithformat:@"%d天",days];
            }
            if (hours<10) {
              self.hourlabel.text = [nsstring stringwithformat:@"0%d",hours];
            }else{
              self.hourlabel.text = [nsstring stringwithformat:@"%d",hours];
            }
            if (minute<10) {
              self.minutelabel.text = [nsstring stringwithformat:@"0%d",minute];
            }else{
              self.minutelabel.text = [nsstring stringwithformat:@"%d",minute];
            }
            if (second<10) {
              self.secondlabel.text = [nsstring stringwithformat:@"0%d",second];
            }else{
              self.secondlabel.text = [nsstring stringwithformat:@"%d",second];
            }

          });
          timeout--;
        }
      });
      dispatch_resume(_timer);
    }
  }


}

3.在需要出使用:

[self downsecondhandle:@"1494622800000"];

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。