C# ini settings read and write example

Program.cs

using System;
using System.IO;
using System.Runtime.InteropServices;
using System.Text;

namespace RuyutConsoleApp
{
    class Program
    {
        static void Main(string[] args)
        {
            string fileName = "RuyutConsoleApp.ini";
            fileName = Path.GetFullPath(fileName);

            Console.WriteLine("WriteIniFile");
            WriteValueFromIniFile("basic", "k1", "v1", fileName);
            WriteValueFromIniFile("basic", "k2", "中文", fileName);
            WriteValueFromIniFile("進階", "鍵", "值", fileName);

            Console.WriteLine("ReadIniFile");
            string value1 = ReadValueFromIniFile("basic", "k1", "null", fileName);
            string value2 = ReadValueFromIniFile("basic", "k2", "null", fileName);
            string value3 = ReadValueFromIniFile("進階", "鍵", "null", fileName);
            Console.WriteLine(value1);
            Console.WriteLine(value2);
            Console.WriteLine(value3);
        }

        [DllImport("kernel32", CharSet = CharSet.Unicode)]
        private static extern long WritePrivateProfileString(string section, string key, string val, string filePath);

        [DllImport("kernel32", CharSet = CharSet.Unicode)]
        private static extern int GetPrivateProfileString(string section, string key, string def, StringBuilder retVal, int size, string filePath);

        public static void WriteValueFromIniFile(string section, string key, string value, string filePath)
        {
            WritePrivateProfileString(section, key, value, filePath);
        }

        public static string ReadValueFromIniFile(string section, string key, string def, string filePath)
        {
            StringBuilder temp = new StringBuilder(4096);
            int i = GetPrivateProfileString(section, key, def, temp, 4096, filePath);
            return temp.ToString();
        }
    }
}