IniFile.cs

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

namespace PresentationPrompter
{
    public class IniFile
    {
        private readonly string _path;

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

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

        public IniFile(string path)
        {
            _path = path;
        }

        public string Read(string section, string key, string defaultValue)
        {
            var sb = new StringBuilder(256);
            GetPrivateProfileString(section, key, defaultValue, sb, 256, _path);
            return sb.ToString();
        }

        public void Write(string section, string key, string value)
        {
            WritePrivateProfileString(section, key, value, _path);
        }

        public int ReadInt(string section, string key, int defaultValue)
        {
            string value = Read(section, key, defaultValue.ToString());
            int result;
            if (int.TryParse(value, out result))
                return result;
            return defaultValue;
        }
    }
}