iOS中封装常见的倒计时（获取验证码、支付倒计时、商城倒计时）

         做一朵白莲花吧，在物欲横流的社会底层静静发育，不沾染一点灰尘，慢慢伸出理想的枝干，穿越尔虞我诈的茂密荷叶，在潋滟的水面上开出洁白的花瓣，笑对阳光，笑对梦雨，笑对秋风，笑对看客，然后结成一个纯净的心灵莲蓬，在里面珍藏洁白如玉的理想莲子。  

         之所以，写这篇文章，是本菜鸟觉得获取验证码倒计时这个知识点貌似、大概、也许，每个App基本上都会遇到的，为了不再写那么都烦躁的代码，所有上来与大家共勉一下，希望大家多多指教。又因为最近项目遇到支付倒计时，所有也把这个方法做了修改一起分享出来。

------------------------------使用方法------------------------------------

一：最常见的：注册、忘记密码的时候获取验证码倒计时

二：支付过程支付时间倒计时、商城活动倒计时

------------------------------.h------------------------------------

#import

@interfaceCountDown :NSObject

///支付过程倒计时商城倒计时

-(void)countDownWithSeparate:(NSInteger)totalTime completeBlock:(void(^)(NSIntegerday,NSIntegerhour,NSIntegerminute,NSIntegersecond))completeBlock;

///获取验证码倒计时

-(void)countDownWithTime:(NSInteger)totalTime completeBlock:(void(^)(NSIntegercountDown))completeBlock;

///主动销毁定时器

-(void)destoryTimer;

@end

------------------------------.m------------------------------------

#import"CountDown.h"

@interfaceCountDown()

@property(nonatomic,retain)dispatch_source_ttimer;

@end

@implementationCountDown

#pragma mark支付过程倒计时    商城倒计时

-(void)countDownWithSeparate:(NSInteger)totalTime completeBlock:(void(^)(NSIntegerday,NSIntegerhour,NSIntegerminute,NSIntegersecond))completeBlock{

if(_timer==nil) {

__blockNSIntegertimeout = totalTime;

if(timeout !=0) {

dispatch_queue_tqueue =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);

dispatch_source_set_event_handler(_timer, ^{

if(timeout <=0){

dispatch_source_cancel(_timer);

_timer=nil;

dispatch_async(dispatch_get_main_queue(), ^{

completeBlock(0,0,0,0);

});

}else{

NSIntegertotalTime = timeout;

NSIntegers =1;

NSIntegerm = s *60;

NSIntegerh = m *60;

NSIntegerd = h *24;

NSIntegerday = totalTime / d;//天

NSIntegerhour = (totalTime - day * d) / h;//时考虑天1天23小时59分钟59秒

//NSInteger onlyhour = totalTime / h;//时不考虑天只考虑到小时28小时59分钟59秒

NSIntegerminute = (totalTime - day * d - hour * h) / m;//分

NSIntegersecond = (totalTime - day * d - hour * h - minute * m) / s;//秒

dispatch_async(dispatch_get_main_queue(), ^{

completeBlock(day,hour,minute,second);

});

//不考虑天的回调28小时59分钟59秒

//dispatch_async(dispatch_get_main_queue(), ^{

//completeBlock(0,onlyhour,minute,second);

//});

timeout--;

}

});

dispatch_resume(_timer);

}

}

}

#pragma mark获取验证码倒计时

-(void)countDownWithTime:(NSInteger)totalTime completeBlock:(void(^)(NSIntegercountDown))completeBlock

{

if(_timer==nil) {

__blockNSIntegertimeout = totalTime;

if(timeout !=0) {

dispatch_queue_tqueue =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);

dispatch_source_set_event_handler(_timer, ^{

if(timeout <=0){

dispatch_source_cancel(_timer);

_timer=nil;

dispatch_async(dispatch_get_main_queue(), ^{

completeBlock(0);

});

}else{

dispatch_async(dispatch_get_main_queue(), ^{

completeBlock(timeout);

});

timeout--;

}

});

dispatch_resume(_timer);

}

}

}

#pragma mark主动销毁定时器

-(void)destoryTimer

{

if(_timer){

dispatch_source_cancel(_timer);

_timer=nil;

}

}

@end