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ProcessFileName

function ProcessFileName(const aFileName: String): String;

Example​

procedure ScriptEvent(var Value: Variant);
begin
  if FileCon <> nil then
    Value := FileCon.ProcessFileName('order-<FILENO>-<YYYY><MM><DD>.xml')
  else
    Value := '';
end;

Usage​

ProcessFileName expands FileCon counters, current definition data and action/system tags in a filename and optionally sanitises it.

Processing order

  1. If <FILENO> exists (case-insensitive), replace every occurrence with the current file number and advance that number once. Reset normally starts it at 1.
  2. If <COUNTER> exists, replace every occurrence with the current separate counter value. This method does not increment that counter; Velox FileSavePath prepares it before generating an output path.
  3. When FileCon belongs to a data definition, replace data-field tags using its current output record.
  4. Process action-local, global, variable, built-in/setup/date, Azure-secret and Velox-constant tags through the context.
  5. Velox normally trims the result and replaces control characters, non-printable or non-ASCII characters, and characters invalid in a Windows filename with -.

Result limitations

The result is a filename string only. This method does not combine it with a directory, make it unique, check reserved device names, enforce filesystem/path length, test access/existence or write a file. Velox FileSavePath performs separate directory combination and optional unique-name handling.

Because slash/backslash/colon are replaced under the default safe-name policy, do not pass a full path expecting it to remain a path. Unicode/non-ASCII filename characters are also replaced by Velox.

State, errors and quirks

  • Evaluating a template containing <FILENO> consumes a number even if no file is later saved. Calls without that tag do not advance it.
  • Direct calls do not advance <COUNTER>; repeated results can share its current value.
  • Data-tag results depend on the owning definition and current output record; a standalone or module-level FileCon skips this pass.
  • General tag expansion can generate a new GUID/ID or resolve mutable time/locals/globals/secrets on each call and can raise for invalid/missing dynamic tags.
  • Unresolved angle-bracket text can be changed by safe-filename conversion after tag processing.
  • The method does not change aFileName, FileName or CurrentFileName, but it can advance the <FILENO> sequence and resolve local-variable tags.

Additional Technical Info​

ProcessFileName expands the filename-specific and general Velox tags in aFileName, then applies the connection's native safe-filename policy.

Security and concurrency

Do not incorporate untrusted separators/traversal text or secrets and assume sanitisation makes the result authorised; directory selection and service permissions are separate. Counter, record and local context are unsynchronised, so do not call concurrently on one FileCon.

Related entries

Created 2026-07-15