细节改进：打开新文件夹时默认显示当前文件夹的上一级文件夹

MusicPlayer2/FilePathHelper.cpp

@@ -52,6 +52,18 @@ wstring CFilePathHelper::GetDir() const
 	return m_file_path.substr(0, index + 1);
 }
 
+wstring CFilePathHelper::GetParentDir() const
+{
+	wstring dir{ GetDir() };
+	size_t index;
+	if (!dir.empty() && (dir.back() == L'\\' || dir.back() == L'/'))
+		dir.pop_back();
+	index = dir.rfind('\\');
+	if (index == wstring::npos)
+		index = dir.rfind('/');
+	return m_file_path.substr(0, index + 1);
+}
+
 const wstring& CFilePathHelper::ReplaceFileExtension(const wchar_t * new_extension)
 {
 	size_t index;

MusicPlayer2/FilePathHelper.h

@@ -13,6 +13,7 @@ public:
 	wstring GetFileName() const;							//获取文件名
 	wstring GetFileNameWithoutExtension() const;			//获取文件名（不含扩展名）
 	wstring GetDir() const;									//获取目录
+	wstring GetParentDir() const;							//获取上级目录
 	wstring GetFilePath() const { return m_file_path; }		//获取完整路径
 	const wstring& ReplaceFileExtension(const wchar_t* new_extension);		//替换文件的扩展名，返回文件完整路径
 protected:

MusicPlayer2/MusicPlayerDlg.cpp

@@ -1866,7 +1866,8 @@ void CMusicPlayerDlg::OnFileOpenFolder()
 	CFolderBrowserDlg folderPickerDlg(this->GetSafeHwnd());
 	folderPickerDlg.SetInfo(_T("请选择一个文件夹，文件夹里的所有音频文件都将添加到播放列表。"));
 #else
-	CFolderPickerDialog folderPickerDlg(theApp.m_player.GetCurrentPath().c_str());
+	CFilePathHelper current_path(theApp.m_player.GetCurrentPath());
+	CFolderPickerDialog folderPickerDlg(current_path.GetParentDir().c_str());
 #endif
 	if (folderPickerDlg.DoModal() == IDOK)
 	{