//Registry.ClassesRoot   對應注冊表 HKEY_CLASSES_ROOT
//Registry.CurrentConfig 對應注冊表 HKEY_CURRENT_CONFIG
//Registry.CurrentUser   對應注冊表 HKEY_CURRENT_USER
//Registry.LocalMachine   對應注冊表 HKEY_LOCAL_MACHINE
//Registry.Users   對應注冊表 HKEY_USERS

using System;
using Microsoft.Win32;
using System.Windows.Forms;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            string temp = null, tempType = null;
            object displayName = null, uninstallString = null, releaseType = null;
            RegistryKey currentKey = null;
            int softNum = 0;
            RegistryKey pregkey = Registry.LocalMachine.OpenSubKey(@"Software\Microsoft\Windows\CurrentVersion\Uninstall");//獲取指定路徑下的鍵
            try
            {
                foreach (string item in pregkey.GetSubKeyNames())               //循環所有子鍵
                {
                    currentKey = pregkey.OpenSubKey(item);
                    displayName = currentKey.GetValue("DisplayName");           //獲取顯示名稱
                    uninstallString = currentKey.GetValue("UninstallString");   //獲取卸載字符串路徑
                    releaseType = currentKey.GetValue("ReleaseType");           //發行類型,值是Security Update為安全更新,Update為更新
                    bool isSecurityUpdate=false;
                    if (releaseType != null)
                    {
                        tempType = releaseType.ToString();
                        if (tempType == "Security Update" || tempType == "Update")
                            isSecurityUpdate = true;
                    }
                    if (!isSecurityUpdate && displayName != null && uninstallString != null)
                    {
                        softNum++;
                        temp += displayName.ToString() + Environment.NewLine;
                    }
                }
            }
            catch (Exception E)
            {
                MessageBox.Show(E.Message.ToString());
            }
            tbSoftWare.Text = "共有軟件" + softNum.ToString() + "個"+ Environment.NewLine + temp;
            pregkey.Close();
        }

    }
}