Getting and setting desktop folder names

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Introduction

For a certain application we were developing, we needed to retrieve the names of some of the common shell folders on the desktop like My Computer, Recycle Bin etc. We soon discovered that by default each OS comes with some pre-defined names depending on what Language version of the OS was used. These strings were stored inside Shell32.dll. But the user was free to rename any of these folders, and when he did that the new strings were stored in the registry. I do not know, how many people will find this code useful, but in case someone ever encounters a situation where he needs to do this, he need not spend the long hours we had to spend before we discovered that this was simply a matter of reading Shell32.dll and the registry. I've written some functions which you can use in your programs directly, by including a single header file.

Typical Usage

// This will retrieve the localized
// names stored in Shell32.dll
cout << "Localized folder names\r\n";
cout << "------------------------------\r\n";
cout << GetLocalizedName(MyComputer) << "\r\n";
cout << GetLocalizedName(MyDocuments) << "\r\n";
cout << GetLocalizedName(NetworkNeighbourhood) << "\r\n";
cout << GetLocalizedName(RecycleBin) << "\r\n";
cout << GetLocalizedName(InternetExplorer) << "\r\n";

cout << "\r\n";

// Let's change the user defined names
// that are stored in the registry
SetCustomName(MyComputer,"Nish's Computer");
SetCustomName(RecycleBin,"Trash Can");

// This retrieves the user defined names
// from the registry
cout << "User-defined folder names\r\n";
cout << "------------------------------\r\n";
cout << GetCustomName(MyComputer) << "\r\n";
cout << GetCustomName(MyDocuments) << "\r\n";
cout << GetCustomName(NetworkNeighbourhood) << "\r\n";
cout << GetCustomName(RecycleBin) << "\r\n";
cout << GetCustomName(InternetExplorer) << "\r\n"; 

The Functions

For all three functions I am using a custom enum to specify the desktop folder

enum IconFolder
{
    MyComputer,
    MyDocuments,
    NetworkNeighbourhood,
    RecycleBin,
    InternetExplorer
};

GetLocalizedName

CString GetLocalizedName(IconFolder folder)
{
    HMODULE sh32lib = LoadLibrary("Shell32.dll");
    char buff[256];

    switch(folder)
    {
    case MyComputer:
        LoadString(sh32lib,9216,buff,255);
        break;
    case MyDocuments:
        LoadString(sh32lib,9227,buff,255);
        break;
    case NetworkNeighbourhood:
        LoadString(sh32lib,9217,buff,255);
        break;
    case RecycleBin:
        LoadString(sh32lib,8964,buff,255);
        break;
    case InternetExplorer:
        LoadString(sh32lib,9222,buff,255);
        break;
    default:
        strcpy(buff,"Invalid Folder Request");
        break;
    }

    FreeLibrary(sh32lib);
    return CString(buff);
}

As you can see, all I do is to load strings from Shell32.dll, the string table entry identifiers are hard coded and I have tested this on Windows XP Home and Professional. I do believe that they will be the same for Windows 2000 versions, but I am not as sure for other OSes like Windows ME. If someone could test it and let me know, that'd be awfully nice.

GetCustomName

CString GetCustomName(IconFolder folder)
{
    HKEY hKey = 0;
    CString keyname = 
        "Software\\Microsoft\\Windows\\CurrentVersion\\Explorer\\CLSID\\";

    switch(folder)
    {
    case MyComputer:
        keyname += "{20D04FE0-3AEA-1069-A2D8-08002B30309D}";
        break;
    case MyDocuments:
        keyname += "{450D8FBA-AD25-11D0-98A8-0800361B1103}";
        break;
    case NetworkNeighbourhood:
        keyname += "{208D2C60-3AEA-1069-A2D7-08002B30309D}";
        break;
    case RecycleBin:
        keyname += "{645FF040-5081-101B-9F08-00AA002F954E}";
        break;
    case InternetExplorer:
        keyname += "{871C5380-42A0-1069-A2EA-08002B30309D}";
        break;
    default:        
        keyname = "";
        break;
    }

    BYTE buff[256];

    if(keyname.GetLength())
    {
        LONG result = ::RegOpenKeyEx(HKEY_CURRENT_USER,
            (LPCTSTR)keyname,0,KEY_READ,&hKey);

        ZeroMemory(buff,255);
        DWORD sz = sizeof buff;
        DWORD typ = REG_SZ;

        RegQueryValueEx(hKey,"",0,&typ,buff,&sz);

        RegCloseKey(hKey);
    }
    else
    {
        return CString("Invalid Folder Request");
    }

    if(CString(buff).GetLength())
        return CString(buff);
    else
        return CString("No custom definition");
}

Well, this is pretty simple too; just a matter of reading some registry entries. Basically this is exactly what the OS does too when it shows the desktop icons, it first reads these registry values and if they are blank, then it will extract the strings out of Shell32.dll.

SetCustomName

void SetCustomName(IconFolder folder, CString foldername)
{
    HKEY hKey = 0;
    CString keyname = 
        "Software\\Microsoft\\Windows\\CurrentVersion\\Explorer\\CLSID\\";

    switch(folder)
    {
    case MyComputer:
        keyname += "{20D04FE0-3AEA-1069-A2D8-08002B30309D}";
        break;
    case MyDocuments:
        keyname += "{450D8FBA-AD25-11D0-98A8-0800361B1103}";
        break;
    case NetworkNeighbourhood:
        keyname += "{208D2C60-3AEA-1069-A2D7-08002B30309D}";
        break;
    case RecycleBin:
        keyname += "{645FF040-5081-101B-9F08-00AA002F954E}";
        break;
    case InternetExplorer:
        keyname += "{871C5380-42A0-1069-A2EA-08002B30309D}";
        break;
    default:        
        keyname = "";
        break;
    }

    if(keyname.GetLength())
    {
        LONG result = ::RegOpenKeyEx(HKEY_CURRENT_USER,
            (LPCTSTR)keyname,0,KEY_WRITE,&hKey);

        RegSetValueEx(hKey,"",0,REG_SZ,
            (const BYTE*)foldername.GetBuffer(0),foldername.GetLength());
        foldername.ReleaseBuffer();

        RegCloseKey(hKey);

        LPITEMIDLIST pidl;
        SHGetSpecialFolderLocation(NULL,CSIDL_DESKTOP,&pidl);
        SHChangeNotify(SHCNE_ASSOCCHANGED,SHCNF_IDLIST,pidl,0);
    }
}

Here, we simply update the registry entries with the new custom strings. If you save a NULL string, then the OS will use the language specific strings from Shell32.dll. There is some interesting bit of code in the end that I use to force a refresh of the desktop icon names. I tried everything from invalidating the desktop, sending WM_PAINT messages to sending F5 key messages, but none of them worked. This was the only code that worked for me.

Refreshing the desktop trick (save this one)

LPITEMIDLIST pidl;
SHGetSpecialFolderLocation(NULL,CSIDL_DESKTOP,&pidl);
SHChangeNotify(SHCNE_ASSOCCHANGED,SHCNF_IDLIST,pidl,0);

Conclusion

The basic problem with using these type of registry reads and DLL string reads is that you never know when Microsoft will change the string identifiers or the registry locations in their next OS versions. But that's a risk you have to live with, and whenever they make a change, you'll have to be prepared to do version checks and do the required stuff depending on the IS versions detected. I do hope at least a few people would have benefited from this articles. Feel free to submit your feedback through the forum at the bottom of this article.