如何修复MFC CStdioFile和CString乱码，同时读取和处理文件中的数据？

问：

Visual Studio 2019 社区版和 MFC

我的代码：

void CTMCVDlg::FileIO()
{
//  Getting source file path to read and destination file path to write
    CString    destpath, sourcepath, destname;
    GetDlgItemText(IDC_EDIT1, sourcepath);
    GetDlgItemText(IDC_EDIT1, destpath);
    GetDlgItemText(IDC_EDIT2, destname);
    destpath = GetFilePathExceptFileName(destpath);
    CStdioFile outF(destpath + destname + _T(".osu"), CFile::modeWrite | CFile::modeCreate);
    CStdioFile inF(sourcepath, CFile::modeRead | CFile::typeBinary);
//    Operation Log
    AppendText3(_T("Created and opened file \"") + filename + _T(".osu\""));
    AppendText3(_T("Converting..."));
/*
*    I want to read the source file line by line and when I meet a line with 'TimingPoints' the loop stops.
*    szline: read file line by line
*    temp: special string for exception of regular options
*    aa: not used
*/
    CStringW szline = _T("");
    CString temp = _T("");
    CStringA aa = "";
    while (inF.ReadString(szline))
    {
        AppendText3(szline);    // Just debug for what it read
        if (szline.Find(_T("Mode:")) != -1)    // If it meets a line including 'Mode:' then write 'Mode: 3'
        {
            temp = _T("Mode: 3");
            outF.Write(temp, temp.GetLength() << 1);
            outF.Write("\r\n", 2);
        }
        else // else write what it has read.
        {
            outF.Write(szline, szline.GetLength() << 1);
            outF.Write("\r\n", 2);
        }
        if (szline.Find(_T("TimingPoints")) != -1)    // if it meets 'TimingPoints' then exit the loop.
        {
            break;
        }
    }
}

输入文件：

输出文件：

调试：

文本文件编码：UTF-8

我想知道，为什么在读取 CString 对象时这一切都变成了乱码？

另外，为什么输出文件有很多多余的空换行符？

此外，我不能让循环结束，因为它找不到“TimingPoints”和“Mode：”关键字。我尝试使用宏将宽字符转换为 UTF-8 字符，但输出文件充满了乱码。CW2A

我想逐行读取输入文件并搜索关键字以进行不同的操作。