C# | check if program/application is installed on remote computer

As an advance to my previous post about checking if a program or an application is installed on my comptuer, I bringing a code for doing this validation on a remote computer.

The code is the same as checking for installed app in local comptuer (as described here) except that checking remote machine registry.
The remote machine registry checking is preformed using the static method OpenRemoteBaseKey of the class RegistryKey.

The code:

public static bool IsAppInstalled(string p_machineName, string p_name)
{
   string keyName;
 
   // search in: CurrentUser
   keyName = @"SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall";
   if (ExistsInRemoteSubKey(p_machineName, RegistryHive.CurrentUser, keyName, "DisplayName", p_name) == true)
   {
      return true;
   }
 
   // search in: LocalMachine_32
   keyName = @"SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall";
   if (ExistsInRemoteSubKey(p_machineName, RegistryHive.LocalMachine, keyName, "DisplayName", p_name) == true)
   {
      return true;
   }
 
   // search in: LocalMachine_64
   keyName = @"SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall";
   if (ExistsInRemoteSubKey(p_machineName, RegistryHive.LocalMachine, keyName, "DisplayName", p_name) == true)
   {
      return true;
   }
 
   return false;
}
private static bool ExistsInRemoteSubKey(string p_machineName, RegistryHive p_hive, string p_subKeyName, string p_attributeName, string p_name)
{
   RegistryKey subkey;
   string displayName;
 
   using (RegistryKey regHive = RegistryKey.OpenRemoteBaseKey(p_hive, p_machineName))
   {
      using (RegistryKey regKey = regHive.OpenSubKey(p_subKeyName))
      {
         if (regKey != null)
         {
            foreach (string kn in regKey.GetSubKeyNames())
            {
               using (subkey = regKey.OpenSubKey(kn))
               {
                  displayName = subkey.GetValue(p_attributeName) as string;
                  if (p_name.Equals(displayName, StringComparison.OrdinalIgnoreCase) == true) // key found!
                  {
                     return true;
                  }
               }
            }
         }
      }
   }
   return false;
}
    

How to use this code:

string MACHINE_NAME = "MY-PC-NAME";
string APPLICATION_NAME = "APP-NAME";
try
{
bool isAppInstalled = IsAppInstalled(MACHINE_NAME, APPLICATION_NAME);
  string msg = string.Format("Application '{0}' is {1} on the remote-machine '{2}'!",
APPLICATION_NAME,
isAppInstalled ? "installed" : "NOT installed",
MACHINE_NAME);
MessageBox.Show(msg);
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}

Enjoy...
MDB-Blog

C# | check if program/application is installed

I searched for a code that getting the list of installed application/programs on my windows pc, but the result wat not satisfying.

I saw that the list of installed programs that i find is NOT like the "Add-Remove Programs" list!!!

The solution is to search for 3 places in registry:

1. SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall inside CurrentUser

2. SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall inside LocalMachine

3. SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall in LocalMachine
And this is my solution...

The Code:

public static bool IsApplictionInstalled(string p_name)
{
    string displayName;
    RegistryKey key;

    // search in: CurrentUser
    key = Registry.CurrentUser.OpenSubKey(@"SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall");
    foreach (String keyName in key.GetSubKeyNames())
    {
        RegistryKey subkey = key.OpenSubKey(keyName);
        displayName = subkey.GetValue("DisplayName") as string;
        if (p_name.Equals(displayName, StringComparison.OrdinalIgnoreCase) == true)
        {
            return true;
        }
    }

    // search in: LocalMachine_32
    key = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall");
    foreach (String keyName in key.GetSubKeyNames())
    {
        RegistryKey subkey = key.OpenSubKey(keyName);
        displayName = subkey.GetValue("DisplayName") as string;
        if (p_name.Equals(displayName, StringComparison.OrdinalIgnoreCase) == true)
        {
            return true;
        }
    }

    // search in: LocalMachine_64
    key = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall");
    foreach (String keyName in key.GetSubKeyNames())
    {
        RegistryKey subkey = key.OpenSubKey(keyName);
        displayName = subkey.GetValue("DisplayName") as string;
        if (p_name.Equals(displayName, StringComparison.OrdinalIgnoreCase) == true)
        {
            return true;
        }
    }

    // NOT FOUND
    return false;
}

This is great for searching for installed / uninstall programs.
I would like for some comments...

Asp.Net - check/validate cookies support

Here is a code for checking/validating that user device (browser) supports cookies. in other words this code checks if cookies are enabled on the browser.

Here the code implemented in the Login page:

    // Constants:
    protected const string QUERYSTRING_CHECK_COOKIE = "checkcookie";
    protected const string TEST_COOKIE_NAME = "check_cookie";
    protected const string TEST_COOKIE_VALUE = "ok";

    // On-load event, at page load:
    protected override void OnLoad(EventArgs p_eventArgs)
    {
        if (IsPostBack == false)
        {
            // Check if browser support cookies
            if (Request[QUERYSTRING_CHECK_COOKIE] == null)
            {
                // try to insert cookie:
                Response.Cookies.Add(new HttpCookie(TEST_COOKIE_NAME, TEST_COOKIE_VALUE));
                string newUrl = string.Format("Login.aspx?{1}=1", QUERYSTRING_CHECK_COOKIE);
                this.Redirect(newUrl, true);
                return;
            }
            else
            {
                // here, client sould contain test cookie:
                HttpCookie cookie = Request.Cookies[TEST_COOKIE_NAME];
                bool isCookieEnabled = cookie != null && cookie.Value == TEST_COOKIE_VALUE;
                if (isCookieEnabled == false)
                {
                    // cookies are disabled!!! show error message
                    Label1.Text = "Device NOT support Cookies!";
                    return;
                }
            }

        }
    }

You can implement this also in other pages than Login page.
:)