pch wiki

Precompiled header file (the general extension is. PCH) is to compile the more stable code in a project in advance and put it in a file (. PCH. these pre-compiled codes can be any C/C ++ code-or even inline functions, but they are relatively stable throughout the project, that is, the code that is not frequently modified during the project development process. Why do we need to pre-compile the header file?

When you create a project in xcode5, the system automatically creates a PCH (precompile prefix header) file named by the project name, during development, you can include widely used header files and Macros in this file, and the compiler automatically adds the header files in the PCH file to all source files, in this way, you can directly use the content in the header file without using import when you need

reminder: PCH precompiled files are no longer automatically created after Xcode6Before Xcode6, create a new project Xcode automatically creates a "project name-prefix.pch" file under the supporting Files folder, which is also a header file, and the contents of the PCH header file can be shared and accessed by all other source files in the project. is a precompiled file.first, let's talk about the role of

How to add a pch file in xcode6,When you create a project in Xcode5, the system automatically creates a pch (Precompile Prefix Header) file named by the project name, during development, you can include widely used header files and Macros in this file, and the compiler automatically adds the header files in the pch file to all source files, in this way, you can d

Swift reads app version information There is time we need to read the app version information such as configuration information, so we can use the method: Nsbundle.mainbundle (). Infodictionary to get Example:SwiftLet infodictionary = Nsbundle.mainbundle (). infodictionaryLet shortversion = infodictionary! ["Cfbundleshortversionstring"]Print (shortversion!)PCH file PCH file name: Generally named after t

When you create a project in Xcode5, the system automatically creates a PCH (precompile Prefix header) file with the name of the project, which you can use to include a widely used header file and a macro in the development process. The compiler will automatically add the header files in the PCH file to all the source files, so that the contents of the header file can be directly used without using import w

1. pch File:PCH means "precompiled header", called Precompiled header file, Xcode6 after the PCH file needs to be added manually, PCH file generally put some basic unchanged code, such as some macro definitions so that the entire project can be used or some framework of the header files.PCH file is designed to improve the efficiency of compilation, a file is modi

Before Xcode6, create a new project Xcode automatically creates a "project name-prefix.pch" file under the supporting Files folder, which is also a header file, and the contents of the PCH header file can be shared and accessed by all other source files in the project. is a precompiled file.First, let's talk about the role of PCH:1. Store some global macros (macros that are used throughout the project)2. Us

before Xcode6, create a new project Xcode automatically creates a "project name-prefix.pch" file under the supporting Files folder, which is also a header file, and the contents of the PCH header file can be shared and accessed by all other source files in the project. is a precompiled file. First, let's talk about the role of PCH:1. Store some global macros (macros that are used throughout the project)2. U

Before Xcode6, create a new project Xcode automatically creates a "project name-prefix.pch" file under the supporting Files folder, which is also a header file, and the contents of the PCH header file can be shared and accessed by all other source files in the project. is a precompiled file.First, let's talk about the role of PCH:1. Store some global macros (macros that are used throughout the project)2. Us

Application Scenarios for PCH files:1. Used to define some global macros2. Used to import some global access to the header file (if only need to let. m or. mm file access, do not need to let. c file access, then you need to write the head file to #ifdef _objc_ #endif之间, because. m and. mm files have a default _objc_ Macros and. c files are not ).3. Use the log from definitionThe contents of the PCH file can

PCH file for iOS learning,1. Overview of PCH files A pch file is a pre-compiled header file (generally with the extension. PCH) That precompiles stable code in a project and stores it in a file (. PCH. These pre-compiled codes can be any C/C ++ code-or even inline function

I. INTRODUCTIONFirst the PCH file (ie: Prefix Header) is a precompiled file that is created automatically by creating a new project before Xcode 6, but after Xcode 6, Apple officially changes the way it is automatically created to manual manually created later;This file is primarily used in project engineering to store the more common and stable classes in which the method resources are shared at development time, without having to refer to their head

Development Tools/Materials:1. Mac2, Xcode (I'm currently using the latest version of Xcode Xcode 7.3) Part of the history of PCH files:Definition: PCH is all called "Precompiled Header", which is the precompiled header file , which helps to save development time and code maintenance time .Development: In the old version of Xcode, after the creation of the project will automatically create a

PCH file is a globally visible file in iOS development, which generally writes the global variables required in the program to the PCH file as a macro definition, such as a screen fit, and how to add a PCH file after X-code6:First Command+n, open the new File window: ios->other->pch file, create a

Before Xcode6, when a new project is created, the system will automatically create a PCH (precompile header) file with the name of the project, and during the development process, the header files that are widely used throughout the project can be included in the file. The compiler will automatically add the header files in the PCH file to all the source files, so that you can use the contents of the header

Before Xcode6, when a new project is created, the system will automatically create a PCH (precompile header) file with the name of the project, and during the development process, the header files that are widely used throughout the project can be included in the file. The compiler will automatically add the header files in the PCH file to all the source files, so that you can use the contents of the header

1. pch File overview PCH file is a precompiled header file (a generic extension of. PCH) is a project in which the more stable code is pre-compiled and placed in a file (. PCH). These pre-compiled code can be any C/s code--or even an inline function--that is more stable throughout the project, i.e. code that i

PCH files can provide some convenience for our programming. is a header file that can be shared and accessed by all other source files in the project, and is suitable for placing global macro definitions and header files.Since Xcode6, the PCH file created by default has been removed, to reduce build time and also to lose convenienceXcode6 How to add a PCH header

1. Click Info.plist Right-click->new file->other->pch file to create PCH filesThe file name is set to: Project Name-prefix-click Create, created successfully.2. Set the PCH file pathSelect item->targets->build settings-> Search in the search box for "Prefix"->apple LLVM 8.0-languagePrecompile Prefix header is set to Yes;Right-