SHFileOperation处理含德语变音符号（Umlaute）路径异常问题

The issue here is that your current implementation relies on the ANSI version of SHFileOperation, which can't handle Unicode characters like German umlauts (ä, ö, ü, ß). Modern Delphi uses UTF-16 string by default, and converting that to AnsiString strips out non-ANSI characters, leaving SHFileOperation with an invalid path.

Here's the corrected version of your function that fully supports Unicode paths:

procedure DeleteToBin(const filename: string);
var
  fileOpStruct: TSHFileOpStructW;
  filenameWide: string;
begin
  // Unicode paths require a double-null terminator
  filenameWide := filename + #0#0;
  // Initialize the struct to avoid garbage values in unused fields
  ZeroMemory(@fileOpStruct, SizeOf(fileOpStruct));
  
  fileOpStruct.Wnd := Application.MainFormHandle;
  fileOpStruct.wFunc := FO_DELETE;
  // Pass the Unicode string directly as a wide char pointer
  fileOpStruct.pFrom := PWideChar(filenameWide);
  // Use bitwise OR instead of addition for flag combinations (safer practice)
  fileOpStruct.fFlags := FOF_ALLOWUNDO or FOF_NOCONFIRMATION;
  
  // Explicitly call the wide-character version of the API
  SHFileOperationW(fileOpStruct);
end;

Key Changes Explained: #

• TSHFileOpStructW: This is the Unicode-aware variant of the file operation struct, designed to handle UTF-16 paths.
• PWideChar: Directly passes the Delphi Unicode string without converting to ANSI, preserving all special characters.
• ZeroMemory: Initializes the struct to zero, preventing unexpected behavior from uninitialized fields (a common source of hard-to-debug issues).
• Bitwise OR: Replaced + with or for combining flags—this is the standard way to set bitmask values and avoids accidental value collisions.

Additional Notes: #

• Make sure your project includes the ShellAPI unit (it's required for SHFileOperationW and related types).
• For older Delphi versions (pre-2009, where string is still ANSI), replace string with WideString and keep the rest of the code the same to maintain Unicode support.

内容的提问来源于stack exchange，提问作者ratmalwer