更换掉系统的NSLog

#pragma mark -
#pragma mark _____Log _________

#ifdef DEBUG
#   define DLog(fmt, ...) NSLog((@"%s [Line %d] " fmt), __PRETTY_FUNCTION__, __LINE__, ##__VA_ARGS__);
#else
#   define DLog(...)
#endif

设置字体加粗

- Bold就是加粗的意思,前面是哪种字体
lb.font = [UIFont fontWithName:@"Helvetica-Bold" size:18];