PrefixHeader.pch文件

PrefixHeader.pch 是一个预编译的文件

New File >> Other >> PCH File  新建PrefixHeader.pch

Targets >> Bulid Setting >> Apple clang - Language 

修改Precompile Prefix Header为YES；

Prefix Header路径设置为 $(SRCROOT)/项目名称/PrefixHeader.pch

代码：

#ifndef PrefixHeader_pch

#define PrefixHeader_pch

// Include any system framework and library headers here that should be included in all compilation units.

// You will also need to set the Prefix Header build setting of one or more of your targets to reference this file.

#ifdef DEBUG

#define MYLog(...) NSLog(__VA_ARGS__)

#else

#define MYLog(...)

#endif

#endif /* PrefixHeader_pch */