iOS 验证码按钮倒计时功能

在app 注册或者登录 需要验证码的地方、为了避免短时间内刷验证码、往往会加上一层验证。

倒计时结束后、可以重新获取！

代码实现如下：

// _countdowntime 倒计时总时间；
//_timer 定时器
- (void)starttime:(uibutton *)verificationcodebutton 
{
 __block nsinteger timeout = [_countdowntime integervalue];
 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);
 dispatch_source_set_event_handler(_timer, ^{
  if(timeout<=0){
   dispatch_source_cancel(_timer);
   dispatch_async(dispatch_get_main_queue(), ^{
    [verificationcodebutton settitle:@"重新获取" forstate:uicontrolstatenormal];
    verificationcodebutton.userinteractionenabled = yes;
    verificationcodebutton.alpha = 1.0;
    verificationcodebutton.backgroundcolor = [uicolor whitecolor];
   });
  } else {
   nsstring *strtime = [nsstring stringwithformat:@"%lds", (long)timeout];
   dispatch_async(dispatch_get_main_queue(), ^{
    [verificationcodebutton settitle:strtime forstate:uicontrolstatenormal];
    verificationcodebutton.userinteractionenabled = no;
    verificationcodebutton.backgroundcolor = [uicolor lighttextcolor];
   });
   timeout--;
  }
 });
 dispatch_resume(_timer);
}

总结

以上所述是小编给大家介绍的ios 验证码按钮倒计时功能，希望对大家有所帮助