本程序支持移除 PDF 文件中的编辑和打印保护(Owner Password) 和打开口令(User Password)（若文件有打开口令，需要提供打开口令）， 不支持破解打开口令(User Password)。
可将 PDF 文件或包含 PDF 文件夹拖放至主窗口来添加文件， 也可点击“打开文件”或“打开文件夹”来添加文件。
This program supports removing the editing and printing protection (Owner Password) and opening password (User Password) in PDF files (if the file has an opening password, you need to provide the opening password), and does not support cracking the opening password (User Password).
You can drag and drop PDF files or folders containing PDFs to the main window to add files, or click "打开文件" or "打开文件夹" to add files.
.NET Framework 4.7 或更高版本的 .NET Framework
.NET Framework 4.7 or higher version of .NET Framework