SelectedText function

Extracts the text covered by the active selection through FPDFText_GetText and returns it as a Unicode string. For a cross-page selection, the per-page slices are joined in page order with a #13#10 (CR/LF) separator so the reconstructed text reads like ordinary multi-line content.

Returns an empty string when nothing is selected.

• Available since v1.36.0.
• Allocates a temporary buffer per page slice (Count+1 wide chars) and copies it into the result; called once per Ctrl+C / pop-up Copy / CopySelectionToClipboard, not on every repaint.
• Generated characters (auto-inserted whitespace / CR / LF surfaced by FPDFText_IsGenerated) appear in the result as their literal characters — the same convention used by the lower-level Text(Start, Count) API on TPdfView.