C++ 命令行解析库 tclap 使用方法

本博文由 youngpan1101 出品，转载请注明出处。
文章链接： http://blog.csdn.net/youngpan1101/article/details/73742209
作者： 宋洋鹏（youngpan1101）
邮箱： [email protected]

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简介

• 通过使用 tclap 库，当我们运行 C++ 项目所生成的可执行文件时，可以很方便地进行命令行（运行指令）的解析。
• 【tclap library webpage】
• 【tclap API】

运行步骤

• 下载 【Download】

  下载 tclap-1.2.1.tar.gz ， 然后解压，将 tclap-1.2.1/include/tclap 复制到工程目录下的 3rdParty 文件夹

• 新建 CMake 工程
  

  • CMakeLists.txt

    cmake_minimum_required(VERSION 2.8)
    project( TclapDemo )
    
    include_directories( ${PROJECT_SOURCE_DIR}/3rdParty )
    
    add_executable( main main.cpp )

  • main.cpp

     #include 
     #include 
    
     #include "tclap/CmdLine.h"
    
    //ostringstream 对象用来进行格式化的输出，常用于将各种类型转换为 string 类型
    //ostringstream 只支持 << 操作符
    template<typename T> std::string toString(const T& t){
        std::ostringstream oss;  //创建一个格式化输出流
        oss<//把值传递如流中
        return oss.str();   
    }
    
    //模板函数：将string类型变量转换为常用的数值类型（此方法具有普遍适用性）  
    template <class Type>  
    Type stringToNum(const std::string& str){  
        istringstream iss(str);  
        Type num;  
        iss >> num;  
        return num;      
    }  
    
    int main(int argc,char** argv){
        try {
            // Define the command line object.
            TCLAP::CmdLine cmd("Command description message", ' ', "0.1");
    
            TCLAP::ValueArg<std::string> nameArg("n", "name", "Name to print", false, "Tom", "std::string", cmd);  // Tom is the default value
    
            TCLAP::ValueArg<int> deviceIdArg("c", "cam", "Camera device id", false, 123, "integer", cmd); // 33 is the default value
    
            TCLAP::SwitchArg noShowOutputSw("", "no-show", "Don't show video", cmd, false);   // false is the default value
    
            TCLAP::ValueArg<double> deviceDataArg("d", "data", "data user defined", false, 2.3456, "double", cmd); // 33 is the default value
    
            TCLAP::ValueArg<std::string> initBbArg("b", "boundingbox", "Init Bounding Box", false, "-1,-1,-1,-1", "x,y,w,h", cmd);  // Tom is the default value
    
            // Parse the args.
            cmd.parse( argc, argv );
    
            std::string name = nameArg.getValue();
            std::cout << "My name is: " << name << std::endl;
    
            int camId = deviceIdArg.getValue();
            std::cout << "Camera ID is: " << camId << std::endl;
    
            bool bIsShowVideo = noShowOutputSw.getValue();
            std::cout << "The flag of showing video: " << bIsShowVideo << std::endl;
    
            double data = deviceDataArg.getValue();
            std::cout << "data is: " << data << std::endl;
    
            std::stringstream initBbSs(initBbArg.getValue());
            double initBb[4];
            for (int i = 0; i < 4; ++i)
            {
              std::string singleValueStr;
              getline(initBbSs, singleValueStr, ',');
              initBb[i] = stringToNum<double>(singleValueStr);
            }
            std::cout << "initBb : " << initBb[0] << " " << initBb[1] << " " << initBb[2] << " " << initBb[3] << std::endl;
    
        } catch (TCLAP::ArgException &e) {  // catch any exceptions
            std::cerr << "error: " << e.error() << " for arg " << e.argId() << std::endl; 
        }
    
        return 1;
    }
    

• 输出结果

  hwj@ubuntu:build$ sudo ./main
  My name is: Tom
  Camera ID is: 123
  The flag of showing video: 0
  data is: 2.3456
  initBb : -1 -1 -1 -1

  hwj@ubuntu:build$ sudo ./main -h
  
  USAGE: 
  
     ./main  [-b ] [-d ] [--no-show] [-c ] [-n
             string>] [--] [--version] [-h]
  
  
  Where: 
  
     -b ,  --boundingbox 
       Init Bounding Box
  
     -d ,  --data 
       data user defined
  
     --no-show
       Don't show video
  
     -c <integer>,  --cam 
       Camera device id
  
     -n string>,  --name 
       Name to print
  
     --,  --ignore_rest
       Ignores the rest of the labeled arguments following this flag.
  
     --version
       Displays version information and exits.
  
     -h,  --help
       Displays usage information and exits.
  
  
     Command description message

  hwj@ubuntu:build$ sudo ./main --version
  
  ./main  version: 0.1
  

  hwj@ubuntu:build$ sudo ./main -d 0.2457 --no-show -c 2 -n Mike -b 2,3,4,-12
  My name is: Mike
  Camera ID is: 2
  The flag of showing video: 1
  data is: 0.2457
  initBb : 2 3 4 -12
  

  hwj@ubuntu:build$ sudo ./main --data -0.2457 --no-show --cam 22 -n Mike
  My name is: Mike
  Camera ID is: 22
  The flag of showing video: 1
  data is: -0.2457
  initBb : -1 -1 -1 -1