Get Uninstall Command For a Certain Program in C#

Question

so I am working on this code that returns an uninstall command string to uninstall a certain program. I have seen this code in other questions, but no one seems to have the same problem as me. This is the code:

public static string GetUninstallCommandFor(string productDisplayName)
    {
        RegistryKey localMachine = Registry.LocalMachine;
        string productsRoot = @"SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Products";
        RegistryKey products = localMachine.OpenSubKey(productsRoot);
        string[] productFolders = products.GetSubKeyNames();

        foreach (string p in productFolders)
        {
            RegistryKey installProperties = products.OpenSubKey(p + @"\InstallProperties");
            if (installProperties != null)
            {
                string displayName = (string)installProperties.GetValue("DisplayName");
                if ((displayName != null) && (displayName.Contains(productDisplayName)))
                {
                    string uninstallCommand = (string)installProperties.GetValue("UninstallString");
                    return uninstallCommand;
                }
            }
        }
        return "";
    }

This code returns this error:

System.NullReferenceException: 'Object reference not set to an instance of an object.'

products was null.

I don't know how products can be empty, I did check that subkey and it was full of folders, so how can I solve this problem.

Given that error message, there is zero chance that products is not null. So you'll need to work out whylocalMachine.OpenSubKey(productsRoot); didn't return anything. — Robert Harvey
– Robert Harvey, Commented Jun 22, 2020 at 21:39

David Browne - Microsoft · Accepted Answer · 2020-06-22 21:50:24Z

2

Build for X64. In a 32bit process you're actually reading HKEY_LOCAL_MACHINE\Software\Wow6432Node through registry redirection.

Or you can request an un-redirected view of the registry per: Avoid Registry Wow6432Node Redirection

answered Jun 22, 2020 at 21:50

David Browne - Microsoft

90.7k7 gold badges52 silver badges87 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

Robert Harvey Over a year ago

I think I would have designed OpenSubKey so that it throws a meaningful exception instead of silently returning nothing.

Saymon Over a year ago

Sorry for the late reply I am going to read the link you gave me, and will be back to you.

David Browne - Microsoft Over a year ago

@RobertHarvey agree. It should have used the "TryParse pattern", eg bool TryOpenSubKey(KeyName, out RegistryKey ) if they wanted to avoid throwing exception, but I think that pattern didn't really show up until .NET 2.0.

Collectives™ on Stack Overflow

Get Uninstall Command For a Certain Program in C#

1 Answer 1

3 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

3 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related