How to check if required software is installed ?

string regKey = @"SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall";
using(Microsoft.Win32.RegistryKey regKeyClass = Registry.LocalMachine.OpenSubKey(regKey))
{
    foreach(string subkey_name in regKeyClass.GetSubKeyNames())
    {
        using(regKey subkey = regKeyClass.OpenSubKey(subkey_name))
        {
            Console.WriteLine(subkey.GetValue("DisplayName"));
        }
    }
}