Integrera PDFium VCL Component-flöden i Delphi- och C++Builder-applikationer, eller PDFium LCL Component-flöden i Lazarus/FPC, med källkodskomponenter för visning, rendering, formulär, utskrift, preflight-rapporter och standardinriktad validering.
Den här artikeln är skriven för teams triaging incoming PDFs before routing them to compliance, support, conversion, or data-entry workflows. Den behandlar PDF intake and review workbench som produktionsnära dokumentteknik, inte som ett isolerat komponentanrop.
Den praktiska risken är att intake tools become unreliable when preview, metadata, warnings, annotations, security state, and operator decisions live in separate screens. Därför behöver flödet ett skrivet kontrakt, observerbar diagnostik och realistiska regressionsfiler.
Arkitekturbeslut
Create one intake record per document. intake states such as new, blocked, needs review, ready, rejected, and archived / metadata fields, warnings, thumbnail strategy, and operator notes
- intake states such as new, blocked, needs review, ready, rejected, and archived
- metadata fields, warnings, thumbnail strategy, and operator notes
- routing rules for encrypted, signed, damaged, image-only, or oversized files
- retention policy for original files, previews, reports, and review decisions
Implementeringsflöde
Summarize document risk before routing. Ordningen nedan gör arbetsflödet granskbart för Delphi- och C++Builder-team.
- create an intake record before rendering pages or modifying the file
- collect metadata, security state, page count, text availability, and warnings
- generate thumbnails and preview pages without changing the source document
- surface blockers and recommended routing actions to the operator
- store the final decision with enough evidence for downstream teams
Valideringsbevis
Intake evidence that supports hand-off. Behåll dessa fält tillsammans med utdata eller supportunderlaget.
- source path, hash, page count, metadata, encryption status, and signature status
- warnings for forms, annotations, attachments, damaged objects, or missing text
- operator decision, routing destination, comment, and time of hand-off
- preview generation status and reason when a file cannot be previewed
Preview should explain, not just display
A review workbench should make document facts visible: page count, encryption, forms, annotations, attachments, signatures, metadata, text availability, and validation findings. Operators can then route a file without guessing.
Support package design
Once PDFium Component is deployed, the most valuable support package is the one that explains the input, profile, output, and exact stage that failed.
- source path, hash, page count, metadata, encryption status, and signature status
- warnings for forms, annotations, attachments, damaged objects, or missing text
- operator decision, routing destination, comment, and time of hand-off
- preview generation status and reason when a file cannot be previewed
- terminology snapshot: intake, review workbench, thumbnail, metadata
Tekniska granskningsnoteringar för PDF intake and review workbench
Använd dessa granskningsnoteringar för att säkerställa att funktionen har passerat demo-nivån och kan försvaras under leverans, support och kundeskalering.
- Beslut: intake states such as new, blocked, needs review, ready, rejected, and archived. Implementeringspresspunkt: collect metadata, security state, page count, text availability, and warnings. Acceptansbevis: operator decision, routing destination, comment, and time of hand-off. Regressionsutlösare: oversized files need queue limits and operator feedback rather than silent delays
- Beslut: metadata fields, warnings, thumbnail strategy, and operator notes. Implementeringspresspunkt: generate thumbnails and preview pages without changing the source document. Acceptansbevis: preview generation status and reason when a file cannot be previewed. Regressionsutlösare: password-protected files need a secure credential hand-off or a blocked state
- Beslut: routing rules for encrypted, signed, damaged, image-only, or oversized files. Implementeringspresspunkt: surface blockers and recommended routing actions to the operator. Acceptansbevis: source path, hash, page count, metadata, encryption status, and signature status. Regressionsutlösare: image-only files should not be routed to text extraction without a warning
- Beslut: retention policy for original files, previews, reports, and review decisions. Implementeringspresspunkt: store the final decision with enough evidence for downstream teams. Acceptansbevis: warnings for forms, annotations, attachments, damaged objects, or missing text. Regressionsutlösare: signed documents may require read-only review to preserve trust
- Beslut: intake states such as new, blocked, needs review, ready, rejected, and archived. Implementeringspresspunkt: create an intake record before rendering pages or modifying the file. Acceptansbevis: operator decision, routing destination, comment, and time of hand-off. Regressionsutlösare: oversized files need queue limits and operator feedback rather than silent delays
Gränsfall
- password-protected files need a secure credential hand-off or a blocked state
- image-only files should not be routed to text extraction without a warning
- signed documents may require read-only review to preserve trust
- oversized files need queue limits and operator feedback rather than silent delays
Delphi / C++Builder notes
PDFium Component should sit behind a small service boundary that receives files, streams, profiles, and credentials, then returns output paths, warnings, metrics, and validation status. Important terms include intake, review workbench, thumbnail, metadata, routing, document risk.
Delphi-kodexempel
Följande Delphi-skiss visar en praktisk servicegräns för detta ämne. Håll policykontroller, loggning och validering utanför det smala produktanropet så att arbetsflödet går att testa.
procedure TIntakeWorkbench.OpenForReview(const FileName: string);
begin
PdfView.LoadFromFile(FileName);
FCaseId := CreateReviewCase(FileName, PdfView.PageCount);
FFindings := RunIntakeChecks(PdfView);
RenderThumbnailStrip;
BindFindingsToGrid(FFindings);
end;Produktionschecklista
- Kör arbetsflödet på en tom fil, en normal kundfil och en värstafallfil
- Öppna den genererade PDF-filen med rätt visare, validator, skrivare eller nedströmsapplikation
- Logga produktversion, profilversion, inmatningshash, utdatasökväg, förfluten tid och antal varningar
- Håll lösenord, certifikat, tillfälliga filer och kunddata under tydliga lagringsregler
- Lägg till regressionsdokument när en kundfil avslöjar ett nytt gränsfall
Produktdokumentation
Fler kodexempel
procedure CollectIdentity(Pdf: TPdf; const FilePath: string;
var Rec: TIntakeRecord);
begin
Rec.Title := Pdf.Title; // Info dictionary value
Rec.Author := Pdf.Author;
Rec.CreatedAt := Pdf.CreationDate; // raw PDF date string ("D:2026...")
// An empty Info title does not mean the document is untitled. The
// component does not expose the XMP packet, so probe the raw file
// bytes for the dc:title element before trusting the blank.
if (Rec.Title = '') and FileContainsText(FilePath, 'dc:title') then
Include(Rec.Flags, ifTitleInXmpOnly);
end;procedure CollectRiskSignals(Pdf: TPdf; var Rec: TIntakeRecord);
var
i, PageNo: Integer;
Ext: string;
begin
Rec.IsEncrypted := Assigned(FPDF_GetSecurityHandlerRevision) and
(FPDF_GetSecurityHandlerRevision(Pdf.Document) <> -1);
Rec.HasForms := Pdf.FormType <> ftNone;
Rec.IsXfa := Pdf.FormType = ftXfaFull;
Rec.HasJavaScript := Pdf.JavaScriptActionCount > 0;
// AnnotationCount is a per-page property; walk the pages to total
// it. Loading a page object renders nothing, so this stays cheap.
Rec.Annotations := 0;
for PageNo := 1 to Pdf.PageCount do
begin
Pdf.PageNumber := PageNo;
Inc(Rec.Annotations, Pdf.AnnotationCount);
end;
Rec.Attachments := Pdf.AttachmentCount;
for i := 0 to Rec.Attachments - 1 do
begin
Ext := LowerCase(ExtractFileExt(string(Pdf.AttachmentName[i])));
if (Ext = '.exe') or (Ext = '.js') or (Ext = '.vbs') or (Ext = '.dll') then
Include(Rec.Flags, ifDangerousAttachment);
end;
end;