using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;

namespace WindowsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        //APIの宣言
        [DllImport("shell32.dll")]
        static extern bool SHGetSpecialFolderPath(IntPtr hwndOwner,
           [Out] StringBuilder lpszPath, int nFolder, bool fCreate);

        //API関数で使う特殊フォルダ定数(使うものだけの記述でよい)
        const int CSIDL_DESKTOP = 0x0000;
        const int CSIDL_FAVORITES = 0x0006;
        const int CSIDL_FONTS = 0x0014;
        const int CSIDL_PERSONAL = 0x0005;
        const int CSIDL_PROGRAM_FILES = 0x0026;
        const int CSIDL_PROGRAMS = 0x0002;
        const int CSIDL_STARTUP = 0x0007;
        const int CSIDL_WINDOWS = 0x0024;
        const int CSIDL_NETHOOD = 0x0013;
        const int CSIDL_CONTROLS = 0x0003;
        const int CSIDL_DRIVES = 0x0011;
        const int CSIDL_RECENT = 0x0008;
        const int CSIDL_SENDTO = 0x0009;
        const int CSIDL_APPDATA = 0x001a;
        const int CSIDL_TEMPLATES = 0x0015;
        const int CSIDL_COMMON_STARTMENU = 0x0016;
        const int CSIDL_COMMON_PROGRAMS = 0X0017;
        const int CSIDL_COMMON_STARTUP = 0x0018;
        const int CSIDL_COMMON_DESKTOPDIRECTORY = 0x0019;
        const int CSIDL_COMMON_APPDATA = 0x0023;
        const int CSIDL_COMMON_TEMPLATES = 0x002d;
        const int CSIDL_COMMON_DOCUMENTS = 0x002e;
        const int CSIDL_COMMON_MUSIC = 0x0035;
        const int CSIDL_COMMON_PICTURES = 0x0036;
        const int CSIDL_COMMON_VIDEO = 0x0037;
        const int CSIDL_COMMON_FAVORITES = 0x001f;
        const int CSIDL_COMMON_ADMINTOOLS = 0x002f;
        const int CSIDL_ADMINTOOLS = 0x0030;
        const int CSIDL_MYMUSIC = 0x000d;
        const int CSIDL_MYVIDEO = 0x000e;
        const int CSIDL_LOCAL_APPDATA = 0x001c;
        const int CSIDL_SYSTEM = 0x0025;
        const int CSIDL_PROGRAM_FILES_COMMON = 0x002b;
        const int CSIDL_PROFILE = 0x0028;
        const int CSIDL_MYPICTURES = 0x0027;
        const int CSIDL_INTERNET = 0x0001;

        private string getPath(int folderCSIDL)
        {
            StringBuilder resultPath = new StringBuilder(255);

            SHGetSpecialFolderPath((IntPtr)0, resultPath, 
                folderCSIDL, false);
            return resultPath.ToString();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            //Fontフォルダ
            string spath = getPath(CSIDL_FONTS);
            MessageBox.Show(spath);
        }

        private void button2_Click(object sender, EventArgs e)
        {
            //User-My Documentsフォルダ
            string spath = getPath(CSIDL_PERSONAL);
            MessageBox.Show(spath);
        }

        private void btnDeskTop_Click(object sender, EventArgs e)
        {
            //DESKTOP
            string spath = getPath(CSIDL_DESKTOP);
            MessageBox.Show(spath);
        }

        private void btnFAVORITES_Click(object sender, EventArgs e)
        {
            //お気に入り
            string spath = getPath(CSIDL_FAVORITES);
            MessageBox.Show(spath);
        }

        private void btnPROGRAMFILES_Click(object sender, EventArgs e)
        {
            //Program Files
            string spath = getPath(CSIDL_PROGRAM_FILES);
            MessageBox.Show(spath);
        }

        private void btn_PROGRAMS_Click(object sender, EventArgs e)
        {
            //<Documents and Settings>\<user name>スタートメニュー\プログラム
            string spath = getPath(CSIDL_PROGRAMS);
            MessageBox.Show(spath);
        }
    }
}