Get A List Of Installed Applications Using LINQ And C#

To get a list of installed applications we need to look into registry. Microsoft.Win32 namespace contains objects which can be used to work with Windows Registry. In this post I will show you some code where I use the power of LINQ to retrieve and display a list of all applications installed on a machine.

The basic idea is that we iterate through a collection of RegistryKey objects within LocalMachine\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall. We then open the sub keys and get the DisplayName.

Here is the code:

static void DisplayInstalledApplications()

{

  string registryKey = 

    @"SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall";

  using (Microsoft.Win32.RegistryKey key =

    Registry.LocalMachine.OpenSubKey(registryKey))

  {

    var query = from a in

              key.GetSubKeyNames()

              let r = key.OpenSubKey(a)

              select new

              {

                Application = r.GetValue("DisplayName")

              };

    foreach (var item in query)

    {

      if (item.Application != null)

        Console.WriteLine(item.Application);

    }

  }

}

 

I can also make this a bit more LINQed by removing the foreach loop. It just adds a bit more C# 3.0 flavour to the code and does the retrieval and writing to console in one line.

 

static void DisplayInstalledApplications2()

{

  string registryKey =

    @"SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall";

  using (Microsoft.Win32.RegistryKey key = 

    Registry.LocalMachine.OpenSubKey(registryKey))

  {

    (from a in key.GetSubKeyNames()

    let r = key.OpenSubKey(a)

    select new

    {

      Application = r.GetValue("DisplayName")

    }).ToList()

      .FindAll(c => c.Application != null)

      .ForEach(c => Console.WriteLine(c.Application));

  }

}