Inicpp

What is this C++ library for?

🔥 1.Aims to make INI file processing simple, convenient, and intuitive.

🔥 2.Advancing the enduring excellence of C++ through collaborative innovation.

🔥 3.Let C++ keep simple,easy and free.

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Ⅰ、Project

You can view the project at https://github.com/dujingning/inicpp.git or https://gitee.com/dujingning/inicpp.

* To support open source, please give us a star. For any issues, feel free to open an issue. Thank you very much!

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Ⅱ、Description

The INI header-only library for Modern C++ supports reading, writing, and even commenting. It is easy to use and simplifies working with INI files.

• New Feature : Super Easy Binding to Your Data Structures (For Read).

Supported INI syntax

When reading INI files, inicpp supports these common forms:

• UTF-8 BOM at the beginning of the file.
• Section headers such as [server], [server], and [ server ].
• Key-value lines using = or :, such as port=8080 and host: localhost.
• Empty values in existing files and values written with set(..., ""), such as key=.
• Full-line comments using ; or #, including lines with leading whitespace.
• Inline comments after whitespace, such as key=value ; comment and key=value # comment.
• Comment markers inside quoted or escaped values are preserved, such as text="a ; b" and path=C:\tmp;cache.
• Duplicate keys in the same section, and duplicate section headers, use the last parsed value for the repeated key.

Quoted values are returned as written; inicpp does not automatically remove quotes or unescape values. Write operations preserve the existing LF or CRLF line-ending style, but multiline values, bare keys without = or :, and full formatting-preserving round trips are not supported.

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Ⅲ、Usage

* 0.Simple to use with C++11 or later.

git clone https://github.com/dujingning/inicpp.git

Include inicpp.hpp, declare the inicpp::IniManager class, and you're all set.

1.write example

Write: Set directly to the file.

#include "inicpp.hpp"
#include <iostream>

int main()
{
    inicpp::IniManager _ini("config.ini"); // Load and parse the INI file.

    _ini["server"]["ip"] = "192.168.3.35";
    _ini["server"]["port"] = 554;
    std::cout << _ini["server"]["ip"] << ":"<< _ini["server"]["port"] << std::endl;

    // or set any
    _ini.set("server","ip","127.0.0.1");
    _ini.set("server","port",8080);
    std::cout << _ini["server"]["ip"] << ":"<< _ini["server"]["port"] << std::endl;
}

1.1.deferred write example

By default, set() and operator[] assignment write to the file immediately. If you need to update many values, disable auto flush, update values in memory, and call flush() once.

#include "inicpp.hpp"
#include <iostream>

int main()
{
    inicpp::IniManager _ini("config.ini"); // Load and parse the INI file.

    if (!_ini.setAutoFlush(false))
    {
        return 1;
    }

    _ini.set("server", "ip", "127.0.0.1"); // Memory only.
    _ini.set("server", "port", 8080);       // Memory only.
    _ini["server"]["name"] = "main";        // Memory only.

    if (_ini.isDirty() && !_ini.flush())
    {
        std::cerr << "failed to write config.ini" << std::endl;
        return 1;
    }
}

flush() writes all pending changes to disk through the same backup-based replacement path as immediate writes. The destructor does not call flush(), so callers can handle write failures explicitly. Calling parse() discards unflushed changes and reloads the file. Calling setAutoFlush(true) while changes are pending first attempts to flush() them; it returns false if that write fails.

2.read example

Convert: From string to typed values. operator[] value conversions, including std::string, bool, and get<T>(), throw std::runtime_error when the section/key is missing or conversion fails. Existing empty values are valid and convert to an empty std::string; use toString(), toInt(), and toDouble() for non-throwing default-value reads. bool conversion treats only "0", "false", and "no" as false.

#include "inicpp.hpp"
#include <iostream>

int main()
{
    inicpp::IniManager _ini("config.ini"); // Load and parse the INI file.

    int         port = _ini["server"]["port"];
    std::string ip   = _ini["server"]["ip"];
    std::cout << ip << ":"<< port << std::endl;

    // or get any
    ip   = _ini["server"]["ip"].get<std::string>();
    port = _ini["server"]["port"].get<int>();
    std::cout << ip << ":"<< port << std::endl;
}

3.comment example

Comment: Write comments for key-value pairs.

#include "inicpp.hpp"
#include <iostream>

int main()
{
    inicpp::IniManager _ini("config.ini"); // Load and parse the INI file.

    // comment section/key
    _ini.set("math"/*section*/, "PI"/*key*/, "3.1415926535897932"/*key*/, "This is PI in mathematics."/*comment*/);
    _ini.setComment("server"/*section*/, "port"/*key*/, "this is the listen ip for server."/*comment*/);
}

Comments written through set() or setComment() are prefixed with ; by default. If the comment string already starts with ; or #, that marker is kept.

4.toString()、toInt()、toDouble()

Convert: From string to type without throwing. toString() returns an empty string for missing keys, while toInt() and toDouble() return 0 or 0.0 when the key is missing or conversion fails.

#include "inicpp.hpp"
#include <iostream>

int main()
{
    inicpp::IniManager _ini("config.ini"); // Load and parse the INI file.
    
    _ini.set("server","port","554","this is the listen port for server");
    std::cout << _ini["server"]["port"] << std::endl;

    // toString
    std::string http_port_s = _ini["server"].toString("port");
    std::cout << "to string:\tserver.port = " << http_port_s << std::endl;

    // toDouble
    double http_port_d = _ini["server"].toDouble("port");
    std::cout << "to double:\tserver.port = " << http_port_d << std::endl;

    // toInt
    int http_port_i = _ini["server"].toInt("port");
    std::cout << "to int:\t\tserver.port = " << http_port_i << std::endl;
}

5.isKeyExists()、sectionsList()、sectionMap()

May contain unnamed sections: when keys are at the head of the file.

#include "inicpp.hpp"
#include <iostream>
#include <iomanip>

// ANSI escape code for green text
#define GREEN_TEXT "\033[1;32m"
#define RESET_COLOR "\033[0m"

int main()
{
    inicpp::IniManager _ini("config.ini"); // Load and parse the INI file.

    for (auto &sectionName : _ini.sectionsList())
    {
        std::cout << GREEN_TEXT << "\nSection: " << RESET_COLOR << sectionName << "\n";

        for (auto &kv : _ini.sectionMap(sectionName))
        {
            std::cout << std::setw(10) << std::left << kv.first
                        << " -------> "
                        << kv.second << std::endl;
        }
    }
}

6.std::wstring

#ifndef _ENBABLE_INICPP_STD_WSTRING_
#define _ENBABLE_INICPP_STD_WSTRING_ // std::wstring support
#endif

#include "inicpp.hpp"

#include <bits/stdc++.h>

int main()
{
    {
        inicpp::IniManager _ini(L"config.ini"); // Load and parse the INI file.
        std::wstring ws = _ini["server"].toWString("info");
        int port = _ini["server"]["port"];
        std::string ip = _ini["server"]["ip"];

        std::cout << ip << ":" << port << std::endl;
    }
    // or
    {
        inicpp::IniManager _ini;
        _ini.setFileName(L"config.ini");
        _ini.parse();
        std::wstring ws = _ini["server"].toWString("info");
        int port = _ini["server"]["port"];
        std::string ip = _ini["server"]["ip"];

        std::cout << ip << ":" << port << std::endl;
    }
}

7.Super Easy Binding to Your Data Structures (Read).

config.ini :

title=config.ini
[server]
isKeepalived=true
;this is the listen ip for server.
port=8080
ip=127.0.0.1


[math]
;Comment: This is pi in mathematics.
PI=3.141592653589793238462643383279502884

config.cpp

#include "inicpp.hpp"
#include <iostream>
#include <iomanip>

#define CONFIG_FILE "config.ini"

class app
{
public:
	typedef struct Config
	{
		typedef struct Server
		{
			std::string ip;
			unsigned short port;
			bool isKeepalived;
		} Server;

		std::string title;
		Server server;
		double PI;
	} Config;

	static const Config readConfig()
	{
		inicpp::IniManager _ini(CONFIG_FILE);

		return Config{
			_ini[""]["title"],
			Config::Server{
				_ini["server"]["ip"],
				_ini["server"]["port"],
				_ini["server"]["isKeepalived"]},
			_ini["math"]["PI"],
		};
	}
};

int main()
{
	/** easy read for app as struct */
	app::Config config = app::readConfig();

	std::cout << config.server.ip << std::endl;

	return 0;
}

8.how to use example/main.cpp

You can compile it using example/Makefile or any other method you prefer.

If make is not available, use the following command: g++ -I../ -std=c++11 main.cpp -o iniExample.

• Compile example/main.cpp

jn@jn:~/inicpp/example$ ls
example  inicpp.hpp  LICENSE  README.md
jn@jn:~/inicpp/example$ cd example/
jn@jn:~/inicpp/example$ make
g++ -I../ -std=c++11 main.cpp -o iniExample
jn@jn:~/inicpp/example$ ls
iniExample  main.cpp  Makefile

• Run example app iniExample

jn@jn:~/inicpp/example$ ./iniExample

Section:
title      -------> config.ini

Section: math
PI         -------> 3.141592653589793238462643383279502884

Section: server
info       -------> the server socket info.
ip         -------> 127.0.0.1
keepalived -------> true
number     -------> 1
port       -------> 8080
jn@jn:~/inicpp/example$

• Configuration file config.ini has been created.

jn@jn:~/inicpp/example$ ls
config.ini  iniExample  main.cpp  Makefile
jn@jn:~/inicpp/example$ cat config.ini
;This is the title.
t