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Registry.ClassesRoot Field

Defines the types (or classes) of documents and the properties associated with those types. This field reads the Windows registry base key HKEY_CLASSES_ROOT.

Namespace:  Microsoft.Win32
Assembly:  mscorlib (in mscorlib.dll)

public static readonly RegistryKey ClassesRoot

Both conventional applications and OLE applications use data that is stored under this key. This key also provides backward compatibility with the Windows 3.1 registration database by storing information for DDE and OLE support. File viewers and user interface extensions store their OLE class identifiers in this key, and processing servers are registered in this key.

The following example demonstrates how to retrieve the subkeys of this key, and prints their names to the screen. Use the OpenSubKey method to create an instance of the particular subkey of interest. You can then use other operations in RegistryKey to manipulate that key.


using System;
using Microsoft.Win32;

class Reg {
    public static void Main() {

        // Create a RegistryKey, which will access the HKEY_CLASSES_ROOT
        // key in the registry of this machine.
        RegistryKey rk = Registry.ClassesRoot;

        // Print out the keys.
        PrintKeys(rk);
    }

    static void PrintKeys(RegistryKey rkey) {

        // Retrieve all the subkeys for the specified key.
        String [] names = rkey.GetSubKeyNames();

        int icount = 0;

        Console.WriteLine("Subkeys of " + rkey.Name);
        Console.WriteLine("-----------------------------------------------");

        // Print the contents of the array to the console.
        foreach (String s in names) {
            Console.WriteLine(s);

            // The following code puts a limit on the number
            // of keys displayed.  Comment it out to print the
            // complete list.
            icount++;
            if (icount >= 10)
                break;
        }
    }
}


.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
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