Download the DSOFILE installation package on Microsoft website, register the dsofile.dll file after installation. Open Delphi 7.0, import this OLE from the menu "Project" -> "Import Type Library". New projects, select ToledocumentProperties from the control ActiveX page to the form, read modifications to the file summary attribute.
Procedure TFORM1.BUTTON1CLICK (Sender: TOBJECT);
VAR
Sp: summaryproperties;
Begin
OledocumentProperties1.Open ('c: /123.pdf', transue, dsoptionopenreadonlyifnowriteAccess);
SP: = OledocumentProperties1.summaryProperties;
Memo1.Lines.Add ('Title:' sp.title);
Memo1.Lines.Add ('Subject:' sp.SUBJECT);
Memo1.Lines.Add ('category:' sp.category);
Memo1.Lines.Add ('Author:' sp.author);
Memo1.Lines.Add ('Keywords:' sp.Keywords);
Memo1.Lines.Add ('Comments:' sp.comments);
OLEDocumentproperties1.close (false);
END;