Delphi Code - Search and Replace Text in Microsoft Word

procedure TForm1.SearchAndReplaceTextInMicrosoftWord(Sender: TObject);
var
   WordFileName, WordFileNameNew, TargetText, ReplacementText: String;
   FoundAndReplaced: Boolean;
   WordApplication, WordFile: Variant;
begin
     //be sure ComObj and Variants units are included in the "uses" clause

     WordFileName := 'C:\PhysiologyWeb\delphi_code_examples\word_file.docx';        //replace file name with the name of your file
     WordFileNameNew := 'C:\PhysiologyWeb\delphi_code_examples\word_file_new.docx'; //replace file name with the name of your file
     TargetText := '';
     ReplacementText := '';

     FoundAndReplaced := False;

     WordApplication := Null;
     WordFile := Null;

     try
        //create Word OLE
        WordApplication := CreateOleObject('Word.Application');
     except
           WordApplication := Null;
           //add error/exception handling code as desired
     end;

     If VarIsNull(WordApplication) = False then
        begin
             try
                WordApplication.Visible := True; //set to False if you do not want to see the activity in the background
                WordApplication.DisplayAlerts := False; //ensures message dialogs do not interrupt the flow of your automation process. May be helpful to set to True during testing and debugging.

                //Open Word File
                try
                   WordFile := WordApplication.Documents.Open(WordFileName);
                   //reference
                   //https://docs.microsoft.com/en-us/office/vba/api/word.documents.open
                except
                      WordFile := Null;
                      //add error/exception handling code as desired
                end;

                If VarIsNull(WordFile) = False then
                   begin
                        WordFile.Content.Find.ClearFormatting;
                        WordFile.Content.Find.Replacement.ClearFormatting;

                        TargetText := 'target text';
                        ReplacementText := 'replacement text';

                        FoundAndReplaced := False;

                        FoundAndReplaced := WordFile.Content.Find.Execute(TargetText,True,EmptyParam,EmptyParam,EmptyParam,EmptyParam,EmptyParam,EmptyParam,EmptyParam,ReplacementText,2,EmptyParam,EmptyParam,EmptyParam,EmptyParam);
                        //reference
                        //https://docs.microsoft.com/en-us/office/vba/api/word.find.execute
                        //here are all the optional parameters
                        //FindText, MatchCase, MatchWholeWord, MatchWildcards, MatchSoundsLike, MatchAllWordForms, Forward, Wrap, Format, ReplaceWith, Replace, MatchKashida, MatchDiacritics, MatchAlefHamza, MatchControl

                        If FoundAndReplaced = False then
                           begin
                                //insert relevant code
                           end;

                        WordFile.SaveAs(WordFileNameNew);
                        //reference
                        //https://docs.microsoft.com/en-us/office/vba/api/word.documents.save
                   end;
             finally
                    WordFile.Close;
                    WordApplication.DisplayAlerts := True;
                    WordApplication.Quit;

                    WordFile := Unassigned;
                    WordApplication := Unassigned;
             end;
        end;
end;