岁月逝，斯人老！

CoreData双向关系/删除规则

http://blog.youkuaiyun.com/rossini23/article/details/5424850

GCD大神的总结Apple inc1. 关于Block void (^loggerBlock)(void); // 声明一个Block loggerBlock =^{ //add your code } ; 2、关于变量 在block中可以使用定义程序块可以访问的变量，但此时Block中的变量只是定义程序块可以访问的变量的一个COPY ,若要共享定义

dispatch_source_t一共有一下几种类型（dispatch_source_type_t):监控进程：DISPATCH_SOURCE_TYPE_PROC,定时器：DISPATCH_SOURCE_TYPE_TIMER,从描述符中读取数据：DISPATCH_SOURCE_TYPE_READ,向描述符中写入字符：DISPATCH_SOURCE_TYPE_WRITE,监控

UIGraphicsBeginImageContext(CGSizeMake(200, 200)); //创建位图上下文 CGContextRef ctx = UIGraphicsGetCurrentContext(); //返回当前上下文 CGContextBeginPath(ctx);//创建新路径 CGRect rect = CGRectMake(0, 0, 80,

NSFetchedResultsController的使用http://my.oschina.net/jackyyang/blog/69680

CFAbsoluteTime start = CFAbsoluteTimeGetCurrent(); // do something CFAbsoluteTime end = CFAbsoluteTimeGetCurrent(); NSLog(@"time cost: %0.3f", end - start);

http://dangpu.sinaapp.com/?p=119https://developer.apple.com/library/mac/#documentation/Cocoa/Conceptual/ObjCRuntimeGuide/Articles/ocrtHowMessagingWorks.html#//apple_ref/doc/uid/TP40008048-CH104-SW1