PDFiumPas-kehittäjäviite

Component: TPdf · Unit: PDFium

Renderöi minkä tahansa ykköspohjaisen sivun bittikartaksi, joka mahtuu pyydettyihin pikkukuvan rajoihin

Syntax

function RenderPageThumbnail(PageIndex, MaxWidth, MaxHeight: Integer): TBitmap;

Parameters

PageIndex	`Integer` - One-based page index to render
MaxWidth	`Integer` - Maximum thumbnail width in pixels
MaxHeight	`Integer` - Maximum thumbnail height in pixels

Return Value

A caller-owned TBitmap, or nil when the document is inactive, the page index is invalid, or the requested size is not positive

Description

The method loads the requested page temporarily, preserves the page aspect ratio, renders the thumbnail on a white background, and closes the temporary page handle before returning

It does not change PageNumber, replace the current loaded page, or fire page-change notifications

Remarks

API names, type names, file names, and PDF terms keep their original spelling so code search remains reliable
Use this for thumbnail strips or navigation panels that must not disturb the editing state of the main TPdf instance

Example

Bmp := Pdf1.RenderPageThumbnail(3, 180, 240);
try
  if Bmp <> nil then
    Image1.Picture.Assign(Bmp);
finally
  Bmp.Free;
end;

RenderPageThumbnail-metodi