@implementation ForgetViewController {        __strong NSTimer * timer;    NSInteger          secondes;        }- (void)dealloc{        if(timer != nil){        [timer invalidate];        timer = nil;    }}secondes= 59;                if (!timer) {                    timer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(timerFired:) userInfo:nil repeats:YES];                    [[NSRunLoop currentRunLoop] addTimer:timer forMode:NSRunLoopCommonModes];                    [timer fire];-(void)timerFired:(id) sender{    if(secondes <=0) {        self.codeBtn.enabled = YES;        [self.codeBtn setTitle:@"重新获取" forState:UIControlStateNormal];    } else {        NSString * title = [NSString stringWithFormat:@"(%lds)后重发", secondes];        [self.codeBtn setTitle:title forState:UIControlStateNormal];    }    secondes--;}