what is wrong with this code?

[dekelc]

hello!

I have written a code that writes and reads from the registry.
to write:

        // Create a new key under HKEY_LOCAL_MACHINE\Software as MCBInc
       RegistryKey key = Registry.LocalMachine.OpenSubKey("Software", true);
        // Add one more sub key
       RegistryKey newkey = key.CreateSubKey("reg");
        // Set value of sub key
        newkey.SetValue("reg", toWrite);

to read:

        // Create a new key under HKEY_LOCAL_MACHINE\Software as MCBInc
        RegistryKey key = Registry.LocalMachine.OpenSubKey("Software", true);
        // Get sub key
        RegistryKey newkey = key.OpenSubKey("reg");
        // Get value of sub key
        return ((string)key.GetValue("reg"));

the problem is, that I can't read what I wrote! I am able to write to registry.

what is wrong?

thanks!

[RFKevdog]

// Create a new key under HKEY_LOCAL_MACHINE\Software as MCBInc
RegistryKey key = Registry.LocalMachine.OpenSubKey("Software", true);
// Get sub key
RegistryKey newkey = key.OpenSubKey("reg");
// Get value of sub key
return ((string)key.GetValue("reg"));



I think you need (string) newkey.GetValue("reg") in that last line..
I tried and it worked

[jcis]

Here a good article showing how to do it..
http://www.csharphelp.com/archives2/archive430.html

[dekelc]

I have anothe question...

How can I know if the registry key even exists?

thanks

[jmcilhinney]

The OpenSubKey method returns null if the specified key does not exist. GetValue does the same. The RegistryKey class also has GetSubKeyNames and GetValueNames methods you can use to get a String array of all subkey and value names. Let me also add that .NET apps should generally avoid using the registry to store their own data if possible.

[dekelc]

why should they avoid using the registry?

[jmcilhinney]

The registry is basically out of control. It now contains so much data, and much of it useless, that it can be a reason that computers run at less than optimum efficiency. To reduce the dependency of applications on the registry Microsoft recommends using XML as much as is practically possible for each application to store there own data locally. The application config file and serialisation are two of the tools available to you to implement this. I'm not sure exactly how things have changed in C# 2005 but VB 2005 has made the process of persisting application ridiculously simple through the My.Settings object. I'd assume that improvements have been made to config file handling in C# 2005 has improved as well, although there are many examples on the Net of how to replicate the My namespace in C# because it is such a great tool.