AnsiString __fastcall GetSystemFolder(AnsiString Value)
{
    TRegistry *R = new TRegistry();

    R->RootKey = HKEY_CURRENT_USER;
    AnsiString Res;
    try{
        R->OpenKeyReadOnly("\\Software\\Microsoft\\Windows\\CurrentVersion\\Explorer\\User Shell Folders");
        Res = R->ReadString(Value);
        if(1 <= Res.AnsiPos("%USERPROFILE%")){
            char buf[MAX_PATH];
            GetEnvironmentVariable("USERPROFILE",buf,MAX_PATH);
            Res = ReplaceText(Res,"%USERPROFILE%",buf);
        }
    }catch(...){
    }
    if(Res.IsEmpty()){
        try{
            R->OpenKeyReadOnly("\\Software\\Microsoft\\Windows\\CurrentVersion\\Explorer\\Shell Folders");
            Res = R->ReadString(Value);
        }catch(...){
        }
    }
    if(!Res.IsEmpty() && Res[Res.Length()] != '\\'){
        Res += '\\';
    }
    delete R;
    return Res;
}

デスクトップや送るメニューのフォルダを取得する関数。

GetSystemFolder("Desktop")

などと使う。