iOS常用宏定义

柔情只为你懂 2023-10-17 08:23 13阅读 0赞

**1.获取屏幕宽度与高度**

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      <code>#define&nbsp;SCREEN_WIDTH&nbsp;&nbsp;&nbsp;[UIScreen&nbsp;mainScreen].bounds.size.width</code> 
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      <code>#define&nbsp;SCREENH_HEIGHT&nbsp;[UIScreen&nbsp;mainScreen].bounds.size.height</code> 
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根据一个网友脱离语言提醒, 如果支持横屏可以用下面的宏:

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      <code>#if&nbsp;__IPHONE_OS_VERSION_MAX_ALLOWED&nbsp;&gt;=&nbsp;80000&nbsp;//&nbsp;当前Xcode支持iOS8及以上</code> 
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      <code>#define&nbsp;SCREEN_WIDTH&nbsp;([[UIScreen&nbsp;mainScreen]&nbsp;respondsToSelector:@selector(nativeBounds)]?[UIScreen&nbsp;mainScreen].nativeBounds.size.width/[UIScreen&nbsp;mainScreen].nativeScale:[UIScreen&nbsp;mainScreen].bounds.size.width)</code> 
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      <code>#define&nbsp;SCREENH_HEIGHT&nbsp;([[UIScreen&nbsp;mainScreen]&nbsp;respondsToSelector:@selector(nativeBounds)]?[UIScreen&nbsp;mainScreen].nativeBounds.size.height/[UIScreen&nbsp;mainScreen].nativeScale:[UIScreen&nbsp;mainScreen].bounds.size.height)</code> 
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      <code>#define&nbsp;SCREEN_SIZE&nbsp;([[UIScreen&nbsp;mainScreen]&nbsp;respondsToSelector:@selector(nativeBounds)]?CGSizeMake([UIScreen&nbsp;mainScreen].nativeBounds.size.width/[UIScreen&nbsp;mainScreen].nativeScale,[UIScreen&nbsp;mainScreen].nativeBounds.size.height/[UIScreen&nbsp;mainScreen].nativeScale):[UIScreen&nbsp;mainScreen].bounds.size)</code> 
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      <code>#else</code> 
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      <code>#define&nbsp;SCREEN_WIDTH&nbsp;[UIScreen&nbsp;mainScreen].bounds.size.width</code> 
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      <code>#define&nbsp;SCREENH_HEIGHT&nbsp;[UIScreen&nbsp;mainScreen].bounds.size.height</code> 
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      <code>#define&nbsp;SCREEN_SIZE&nbsp;[UIScreen&nbsp;mainScreen].bounds.size</code> 
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      <code>#endif</code> 
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**2.获取通知中心**

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      <code>#define&nbsp;LRNotificationCenter&nbsp;[NSNotificationCenter&nbsp;defaultCenter]</code> 
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**3.设置随机颜色**

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      <code>#define&nbsp;LRRandomColor&nbsp;[UIColor&nbsp;colorWithRed:arc4random_uniform(256)/255.0&nbsp;green:arc4random_uniform(256)/255.0&nbsp;blue:arc4random_uniform(256)/255.0&nbsp;alpha:1.0]</code> 
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**4.设置RGB颜色/设置RGBA颜色**

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      <code>#define&nbsp;LRRGBColor(r,&nbsp;g,&nbsp;b)&nbsp;[UIColor&nbsp;colorWithRed:(r)/255.0&nbsp;green:(g)/255.0&nbsp;blue:(b)/255.0&nbsp;alpha:1.0]</code> 
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      <code>#define&nbsp;LRRGBAColor(r,&nbsp;g,&nbsp;b,&nbsp;a)&nbsp;[UIColor&nbsp;colorWithRed:(r)/255.0&nbsp;green:(r)/255.0&nbsp;blue:(r)/255.0&nbsp;alpha:a]</code> 
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      <code>//&nbsp;clear背景颜色</code> 
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      <code>#define&nbsp;LRClearColor&nbsp;[UIColor&nbsp;clearColor]</code> 
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**5.自定义高效率的 NSLog**

项目开发中，我们会在许多地方加上Log，但是发布的时候又不想用这些Log，我们也不可能一个一个的删除，所以自定义Log是必然的！

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      <code>#ifdef&nbsp;DEBUG</code> 
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      <code>#define&nbsp;LRLog(...)&nbsp;NSLog(@"%s&nbsp;第%d行&nbsp;\n&nbsp;%@\n\n",__func__,__LINE__,[NSString&nbsp;stringWithFormat:__VA_ARGS__])</code> 
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      <code>#else</code> 
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      <code>#define&nbsp;LRLog(...)</code> 
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      <code>#endif</code> 
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**6.弱引用/强引用**

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      <code>#define&nbsp;LRWeakSelf(type)&nbsp;&nbsp;__weak&nbsp;typeof(type)&nbsp;weak##type&nbsp;=&nbsp;type;</code> 
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      <code>#define&nbsp;LRStrongSelf(type)&nbsp;&nbsp;__strong&nbsp;typeof(type)&nbsp;type&nbsp;=&nbsp;weak##type;</code> 
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![QQ截图20160712183634.png][QQ_20160712183634.png]

第二种使用方法，定义完弱引用宏之后，直接敲weak.png

**7.设置 view 圆角和边框**

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      <code>#define&nbsp;LRViewBorderRadius(View,&nbsp;Radius,&nbsp;Width,&nbsp;Color)\</code> 
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      <code>\</code> 
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      <code>[View.layer&nbsp;setCornerRadius:(Radius)];\</code> 
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      <code>[View.layer&nbsp;setMasksToBounds:YES];\</code> 
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      <code>[View.layer&nbsp;setBorderWidth:(Width)];\</code> 
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      <code>[View.layer&nbsp;setBorderColor:[Color&nbsp;CGColor]]</code> 
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**8.由角度转换弧度 由弧度转换角度**

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      <code>#define&nbsp;LRDegreesToRadian(x)&nbsp;(M_PI&nbsp;*&nbsp;(x)&nbsp;/&nbsp;180.0)</code> 
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      <code>#define&nbsp;LRRadianToDegrees(radian)&nbsp;(radian*180.0)/(M_PI)</code> 
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**9.设置加载提示框（第三方框架：Toast）**

此宏定义非常好用，但是小伙伴需要CocoaPods导入第三方框架：Toast

使用方法如下：

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      <code>LRToast(@</code> 
      <code>"网络加载失败"</code> 
      <code>);</code> 
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      <code>#define&nbsp;LRToast(str)&nbsp;&nbsp;CSToastStyle&nbsp;*style&nbsp;=&nbsp;[[CSToastStyle&nbsp;alloc]&nbsp;initWithDefaultStyle];&nbsp;\</code> 
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      <code>[kWindow&nbsp;&nbsp;makeToast:str&nbsp;duration:0.6&nbsp;position:CSToastPositionCenter&nbsp;style:style];\</code> 
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      <code>kWindow.userInteractionEnabled&nbsp;=&nbsp;NO;&nbsp;\</code> 
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      <code>dispatch_after(dispatch_time(DISPATCH_TIME_NOW,&nbsp;(int64_t)(0.6&nbsp;*&nbsp;NSEC_PER_SEC)),&nbsp;dispatch_get_main_queue(),&nbsp;^{\</code> 
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      <code>kWindow.userInteractionEnabled&nbsp;=&nbsp;YES;\</code> 
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      <code>});\</code> 
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**10.设置加载提示框（第三方框架：MBProgressHUD）**

此宏定义同上一个类似，如下图：

![QQ截图20160712183716.png][QQ_20160712183716.png]

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      <code>//&nbsp;加载</code> 
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      <code>#define&nbsp;kShowNetworkActivityIndicator()&nbsp;[UIApplication&nbsp;sharedApplication].networkActivityIndicatorVisible&nbsp;=&nbsp;YES</code> 
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      <code>//&nbsp;收起加载</code> 
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      <code>#define&nbsp;HideNetworkActivityIndicator()&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[UIApplication&nbsp;sharedApplication].networkActivityIndicatorVisible&nbsp;=&nbsp;NO</code> 
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      <code>//&nbsp;设置加载</code> 
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      <code>#define&nbsp;NetworkActivityIndicatorVisible(x)&nbsp;&nbsp;[UIApplication&nbsp;sharedApplication].networkActivityIndicatorVisible&nbsp;=&nbsp;x</code> 
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      <code>#define&nbsp;kWindow&nbsp;[UIApplication&nbsp;sharedApplication].keyWindow</code> 
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      <code>#define&nbsp;kBackView&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;for&nbsp;(UIView&nbsp;*item&nbsp;in&nbsp;kWindow.subviews)&nbsp;{&nbsp;\</code> 
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      <code>if</code> 
      <code>(item.tag&nbsp;==&nbsp;10000)&nbsp;\</code> 
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      <code>{&nbsp;\</code> 
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      <code>[item&nbsp;removeFromSuperview];&nbsp;\</code> 
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      <code>UIView&nbsp;*&nbsp;aView&nbsp;=&nbsp;[[UIView&nbsp;alloc]&nbsp;init];&nbsp;\</code> 
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      <code>aView.frame&nbsp;=&nbsp;[UIScreen&nbsp;mainScreen].bounds;&nbsp;\</code> 
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      <code>aView.tag&nbsp;=&nbsp;10000;&nbsp;\</code> 
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      <code>aView.backgroundColor&nbsp;=&nbsp;[[UIColor&nbsp;blackColor]&nbsp;colorWithAlphaComponent:0.3];&nbsp;\</code> 
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      <code>[kWindow&nbsp;addSubview:aView];&nbsp;\</code> 
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      <code>}&nbsp;\</code> 
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      <code>}&nbsp;\</code> 
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      <code>#define&nbsp;kShowHUDAndActivity&nbsp;kBackView;[MBProgressHUD&nbsp;showHUDAddedTo:kWindow&nbsp;animated:YES];kShowNetworkActivityIndicator()</code> 
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      <code>#define&nbsp;kHiddenHUD&nbsp;[MBProgressHUD&nbsp;hideAllHUDsForView:kWindow&nbsp;animated:YES]</code> 
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      <code>#define&nbsp;kRemoveBackView&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;for&nbsp;(UIView&nbsp;*item&nbsp;in&nbsp;kWindow.subviews)&nbsp;{&nbsp;\</code> 
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      <code>if</code> 
      <code>(item.tag&nbsp;==&nbsp;10000)&nbsp;\</code> 
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      <code>{&nbsp;\</code> 
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      <code>[UIView&nbsp;animateWithDuration:0.4&nbsp;animations:^{&nbsp;\</code> 
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      <code>item.alpha&nbsp;=&nbsp;0.0;&nbsp;\</code> 
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      <code>}&nbsp;completion:^(BOOL&nbsp;finished)&nbsp;{&nbsp;\</code> 
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      <code>[item&nbsp;removeFromSuperview];&nbsp;\</code> 
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      <code>}];&nbsp;\</code> 
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      <code>}&nbsp;\</code> 
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      <code>}&nbsp;\</code> 
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      <code>#define&nbsp;kHiddenHUDAndAvtivity&nbsp;kRemoveBackView;kHiddenHUD;HideNetworkActivityIndicator()</code> 
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**11.获取view的frame/图片资源**

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      <code>//获取view的frame（不建议使用）</code> 
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      <code>//#define&nbsp;kGetViewWidth(view)&nbsp;&nbsp;view.frame.size.width</code> 
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      <code>//#define&nbsp;kGetViewHeight(view)&nbsp;view.frame.size.height</code> 
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      <code>//#define&nbsp;kGetViewX(view)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;view.frame.origin.x</code> 
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      <code>//#define&nbsp;kGetViewY(view)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;view.frame.origin.y</code> 
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      <code>//获取图片资源</code> 
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      <code>#define&nbsp;kGetImage(imageName)&nbsp;[UIImage&nbsp;imageNamed:[NSString&nbsp;stringWithFormat:@"%@",imageName]]</code> 
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**12.获取当前语言**

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      <code>#define&nbsp;LRCurrentLanguage&nbsp;([[NSLocale&nbsp;preferredLanguages]&nbsp;objectAtIndex:0])</code> 
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**13.使用 ARC 和 MRC**

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      <code>#if&nbsp;__has_feature(objc_arc)</code> 
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      <code>//&nbsp;ARC</code> 
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      <code>#else</code> 
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      <code>//&nbsp;MRC</code> 
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      <code>#endif</code> 
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**14.判断当前的iPhone设备/系统版本**

**15.判断是真机还是模拟器**

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      <code>#if&nbsp;TARGET_OS_IPHONE</code> 
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      <code>//iPhone&nbsp;Device</code> 
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      <code>#endif</code> 
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      <code>#if&nbsp;TARGET_IPHONE_SIMULATOR</code> 
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      <code>//iPhone&nbsp;Simulator</code> 
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      <code>#endif</code> 
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**16.沙盒目录文件**

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      <code>//获取temp</code> 
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      <code>#define&nbsp;kPathTemp&nbsp;NSTemporaryDirectory()</code> 
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      <code>//获取沙盒&nbsp;Document</code> 
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      <code>#define&nbsp;kPathDocument&nbsp;[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,&nbsp;NSUserDomainMask,&nbsp;YES)&nbsp;firstObject]</code> 
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      <code>//获取沙盒&nbsp;Cache</code> 
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      <code>#define&nbsp;kPathCache&nbsp;[NSSearchPathForDirectoriesInDomains(NSCachesDirectory,&nbsp;NSUserDomainMask,&nbsp;YES)&nbsp;firstObject]</code> 
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**17.GCD 的宏定义**

很多小伙伴都非常烦写GCD的方法，所以在此定义为宏使用更加方便简洁！如下图：

![QQ截图20160712183818.png][QQ_20160712183818.png]

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      <code>//GCD&nbsp;-&nbsp;一次性执行</code> 
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      <code>#define&nbsp;kDISPATCH_ONCE_BLOCK(onceBlock)&nbsp;static&nbsp;dispatch_once_t&nbsp;onceToken;&nbsp;dispatch_once(&amp;onceToken,&nbsp;onceBlock);</code> 
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      <code>//GCD&nbsp;-&nbsp;在Main线程上运行</code> 
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      <code>#define&nbsp;kDISPATCH_MAIN_THREAD(mainQueueBlock)&nbsp;dispatch_async(dispatch_get_main_queue(),&nbsp;mainQueueBlock);</code> 
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      <code>//GCD&nbsp;-&nbsp;开启异步线程</code> 
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      <code>#define&nbsp;kDISPATCH_GLOBAL_QUEUE_DEFAULT(globalQueueBlock)&nbsp;dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT,&nbsp;0),&nbsp;globalQueueBlocl);</code> 
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**宏与const 的使用:**

很多小伙伴在定义一个常量字符串，都会定义成一个宏，最典型的例子就是服务器的地址。在此所有用宏定义常量字符的小伙伴以后就用const来定义吧！为什么呢 ？我们看看：

*  宏的用法：一般字符串抽成宏，代码抽成宏使用。
 *  const用法：一般常用的字符串定义成const（对于常量字符串苹果推荐我们使用const）。

**宏与const区别：**

1.编译时刻不同，宏属于预编译 ，const属于编译时刻

2.宏能定义代码，const不能，多个宏对于编译会相对时间较长，影响开发效率，调试过慢，const只会编译一次，缩短编译时间。

3.宏不会检查错误，const会检查错误

通过以上对比，我们以后在开发中如果定义一个常量字符串就用const，定义代码就用宏。我们来看看如何使用const，列举实际项目使用方法如下图：

![QQ截图20160712184025.png][QQ_20160712184025.png]

在上图本人只是简单定义几个常量字符串，我们创建一个类只要在.h和.m中包含\#import 就可以，然后再.h文件声明一个字符串，在.m中实现就可以了，最后把这个类导入PCH文件中，我们就可任意的发挥啦！

[QQ_20160712183634.png]: http://cc.cocimg.com/api/uploads/20160712/1468319802739618.png
[QQ_20160712183716.png]: http://cc.cocimg.com/api/uploads/20160712/1468319843766775.png
[QQ_20160712183818.png]: http://cc.cocimg.com/api/uploads/20160712/1468319997313335.png
[QQ_20160712184025.png]: http://cc.cocimg.com/api/uploads/20160712/1468320037180134.png