How to read Windows Server 2008 in c#

Question

i am trying o read registry value with the following code.

    Label1.Text = Registry.GetValue("HKEY_LOCAL_MACHINE\\SOFTWARE\\Myweb\\ConnectionManager", "ID", null).ToString();

it work fine when i am trying in windows xp but i never works in windows server 2008. any help Please

Answer 1

You are probably running into the issue of the WOW redirector.

You can use the more specialized classes in Microsoft.Win32 for getting either a 64 or 32 bits part of the hive.

 var root = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine
                                   ,RegistryView.Registry32); // or Registry64
 var flk = root.OpenSubKey("SOFTWARE");
 var slk = flk.OpenSubKey("Myweb");
 var tlk = slk.OpenSubKey("ConnectionManager");
 var val = tlk.GetValue("ID");

 Label1.Text = val.ToString();

Or a more general purpose method to get a registry value whatever it takes:

object GetValue64Or32(string path, string ValueKey)
{
     var parts = path.Split('\\');
     RegistryHive hive = RegistryHive.LocalMachine;
     switch(parts[0])
     {
        case "HKEY_LOCAL_MACHINE":
            hive = RegistryHive.LocalMachine;
        break;
        default:
           throw new NotImplementedException();
     }
     foreach(var view in Enum.GetValues(typeof(RegistryView)))
     {
        var key = RegistryKey.OpenBaseKey(hive, (RegistryView) view);
        for(var partIndex=1; partIndex<parts.Length;partIndex++)
        {
           key = key.OpenSubKey(parts[partIndex]);
           if (key == null) break;
        }
        if (key!=null) return key.GetValue(ValueKey);
     }
     return null;
}

Usage:

var value = GetValue64Or32(
               "HKEY_LOCAL_MACHINE\\SOFTWARE\\Myweb\\ConnectionManager"
             , "ID");
Label1.Text = value!=null?value.ToString():"no value found";

If I use this registry file this code works for the 32 bits hive:

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\MyWeb\]

[HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\MyWeb\ConnectionManager\]
"ID"="id 1"

And this works for the 64 bits hive:

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\MyWeb\]

[HKEY_LOCAL_MACHINE\SOFTWARE\MyWeb\ConnectionManager\]
"ID"="id 1"

You can use REG from the commandprompt to verify if your registrypath exists:

reg query HKLM\Software\MyWeb\ConnectionManager /s