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hujingnemo:
不知道为什么打不开
CHM如何改编字体大小 -
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求答案 weiboyuanios@163.com
iOS软件工程师面试题(高级) -
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这个现在已经广泛使用了嘛!
RoboGuice入门 -
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353144886:
非常之详细 美女求认识
sqlite数据类型 datetime处理
If you look in NSObjCRuntime.h (in Foundation) you will see that FOUNDATION_EXPORT compiles to extern in C, extern "C" in C++, and other things in Win32. So, it's a bit more compatible. For most projects, this won't make any difference.
You should create a header file like
// Constants.h
FOUNDATION_EXPORT NSString *const MyFirstConstant;
FOUNDATION_EXPORT NSString *const MySecondConstant;
//etc.
(you can use extern instead of FOUNDATION_EXPORT if your code will not be used in mixed C/C++ environments or on other platforms)
You can include this file in each file that uses the constants or in the pre-compiled header for the project.
You define these constants in a .m file like
// Constants.m
NSString *const MyFirstConstant = @"FirstConstant";
NSString *const MySecondConstant = @"SecondConstant";
Constants.m should be added to your application/framework's target so that it is linked in to the final product.
The advantage of using string constants instead of #define'd constants is that you can test for equality using pointer comparison (stringInstance == MyFirstConstant) which is much faster than string comparison ([stringInstance isEqualToString:MyFirstConstant]) (and easier to read, IMO).
You should create a header file like
// Constants.h
FOUNDATION_EXPORT NSString *const MyFirstConstant;
FOUNDATION_EXPORT NSString *const MySecondConstant;
//etc.
(you can use extern instead of FOUNDATION_EXPORT if your code will not be used in mixed C/C++ environments or on other platforms)
You can include this file in each file that uses the constants or in the pre-compiled header for the project.
You define these constants in a .m file like
// Constants.m
NSString *const MyFirstConstant = @"FirstConstant";
NSString *const MySecondConstant = @"SecondConstant";
Constants.m should be added to your application/framework's target so that it is linked in to the final product.
The advantage of using string constants instead of #define'd constants is that you can test for equality using pointer comparison (stringInstance == MyFirstConstant) which is much faster than string comparison ([stringInstance isEqualToString:MyFirstConstant]) (and easier to read, IMO).
发表评论
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oc为啥不用try catch
2016-03-23 11:56 1371简单的来说,Apple虽然同时提供了错误处理(NSError) ... -
ReactiveCocoa笔记
2016-03-14 12:31 0为什么使用MVVM?为什么使用ReactiveCocoa? 概 ... -
PINCache
2016-01-19 15:11 908PINCache是线程安全的键值缓存框架,用来储存难以获取或重 ... -
Swift设计模式
2015-12-29 12:04 0Swift设计模式 -
Understanding Swift access control
2015-12-29 12:03 0Swift takes an unusual approuac ... -
cocoapods因GEM_HOME升级遇到问题解决办法
2015-12-17 14:40 884Installing CocoaPods on OS X 10 ... -
swift 闭包的比较写法
2015-12-16 11:10 713let names = ["Chris", ... -
iOS 生成二维码,生成条形码图片
2015-12-03 15:44 1421#pragma mark - 生成条形码以及二维码 // ... -
解决cocoapods 更新慢的问题
2015-11-23 17:01 712最近使用CocoaPods来添加第三方类库,无论是执行pod ... -
iOS中级面试题
2015-11-20 15:12 1141OneV‘s Den在博客里出了10道iOS面试题,用他的话是 ... -
cocoapods出错解决方法
2015-11-09 13:09 707自定义GEM_HOME $ mkdir -p $HOME/So ... -
oc时间从美国时间改到中国时间
2015-10-19 14:12 925_formatter = [[NSDateFormatt ... -
27个iOS开发库
2015-07-24 16:10 737超长慎入列表: DZNEmptyDataSet(UI,空表格 ... -
Values of type 'NSInteger' should not be used as format arguments; add an explic
2015-07-24 10:10 802Values of type 'NSInteger' shou ... -
iOS架构心得体会
2015-05-18 18:35 772好的架构不是设计出来的,而是进行出来的。 我的iOS工程架构 ... -
UICollectionView NSInternalInconsistencyException出现的原因
2015-05-11 11:32 3367'NSInternalInconsistencyExcepti ... -
XLForm-iOS表单库
2015-05-08 14:44 876XLForm是最灵活和强大的iOS类库,用于创建动态table ... -
Info.plist Utility Error: “Info.plist couldn't be opened because there is no suc
2015-05-06 16:13 650http://stackoverflow.com/questi ... -
iOS中Autolayout中各种情况的使用的width,height策略
2015-04-30 15:33 643可以总结为: 如果项目不支持横屏显示,使用w:Compac ... -
一句话加上下拉刷新
2015-04-29 18:22 736怎么一句话添加上拉刷新? https://github.co ...
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