float tmpSize = [[SDImageCache sharedImageCache] checkTmpSize];
_clearCacheName = tmpSize >= 1 ? [NSString stringWithFormat:@"清理缓存(%.2fM)",tmpSize] : [NSString stringWithFormat:@"清理缓存(%.2fK)",tmpSize * 1024];
UIAlertController* alert = [UIAlertController alertControllerWithTitle:@"提示"message:_clearCacheName preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction *cancelAction = [UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:nil];
UIAlertAction* defaultAction = [UIAlertAction actionWithTitle:@"确定" style:UIAlertActionStyleDefault handler:^(UIAlertAction * action) {[[SDImageCache sharedImageCache] clearDisk];}];