unit FindReplace;
// FindReplace.pas
// Source: http://www.tek-tips.com/viewthread.cfm?qid=160357
// 18 Nov 2001 "bearsite4"
// Changes by Daniel Marschall, especially to make it compatible with TSynEdit
interface
uses
Windows, Messages, SysUtils, Classes, Dialogs, SynEdit;
type
FindReplaceCommunication = ( frcAlertUser, frcAlertReplace, frcEndReached );
{allows the replace functions to use the find function avoiding alot
of code duplication. frcAlertuser means that when the find function
has reached the end of the text while searching for a word it will pop
up a message saying the word can't be found. frcAlertReplace
tells the find function not to display a message to the user saying that
the word can't be found but instead to set the state to frcEndReached to
let the replace function know it's reached the end of the text}
TReplaceFunc = function ( const S1, S2: string ): Integer;
TFindReplace = class(TComponent)
private
fEditor: TSynEdit; {the richedit or memo component to hook it up to}
fReplaceDialog: TReplaceDialog; {the replace dialog}
fFindDialog: TFindDialog; {the find dialog}
FindActionOnEnd: FindReplaceCommunication; {the action the find function
should take when it reaches the end of the text while searching for the
word}
function TestWholeWord( Sender: TFindDialog; TestString: string ): boolean;
{returns a true or false depending on whether the user chose the whole word
only option and whether or not the word is a whole word. Actually, it can
test multiple words in a single string as well.}
protected
type
TFindDirection = (sdDefault, sdForwards, sdBackwards);
procedure FindForwards( Sender: TFindDialog; start, finish: integer );
{search through the editor in a forwards direction}
procedure FindBackwards( Sender: TFindDialog; start, finish: integer );
{search through the editor in a backwards direction}
{defined event handlers}
procedure OnFind( Sender: TObject ); virtual;
procedure OnReplace( Sender: TObject ); virtual;
{the centralised find/replace functions}
function TryAndMatch( Sender: TFindDialog; index, finish: integer ): boolean; virtual;
function TryAndReplace(dialog: TReplaceDialog): boolean; virtual;
procedure DoReplace(dialog: TReplaceDialog); virtual;
{the replace function that coordinates all the work}
procedure DoReplaceAll(dialog: TReplaceDialog); virtual;
{the replace all function that coordinates all the work}
procedure DoFind(dialog: TFindDialog; direction: TFindDirection);
public
constructor Create( AOwner: TComponent); override;
property FindDialog: TFindDialog read fFindDialog;
property ReplaceDialog: TReplaceDialog read fReplaceDialog;
procedure CloseDialogs;
procedure FindExecute;
{opens the find dialog}
procedure ReplaceExecute;
{opens the replace dialog}
procedure FindContinue;
procedure FindNext;
procedure FindPrev;
procedure GoToLine( LineNumber: integer );
published
property Editor: TSynEdit read fEditor write fEditor;
end;
(*
procedure Register;
*)
implementation
(*
{$R findrep.dcr}
*)
constructor TFindReplace.Create( AOwner: TComponent );
begin
inherited;
{create the find dialog}
fFindDialog := TFindDialog.Create( Self );
{set up the event handlers}
fFindDialog.OnFind := OnFind;
{create the replace dialog}
fReplaceDialog := TReplaceDialog.Create( Self );
{set up the event handlers}
fReplaceDialog.OnReplace := OnReplace;
fReplaceDialog.OnFind := OnFind;
fReplaceDialog.Options := fReplaceDialog.Options + [frHideWholeWord]; // TODO: currently not supported (see below)
{set find's default action on end of text to alert the user.
If a replace function changes this it is it's responsibility
to change it back}
FindActionOnEnd := frcAlertUser;
end;
procedure TFindReplace.FindForwards( Sender: TFindDialog; start, finish: integer );
var
i: integer;
begin
{to find the word we go through the text on a character by character
basis}
for i := start to finish do
if TryAndMatch( Sender, i, finish ) then
{if we've got a match then stop}
Exit;
end;
procedure TFindReplace.FindBackwards( Sender: TFindDialog; start, finish: Integer );
{since only find has a (search) up option and replace doesn't
we don't have to worry about sender since only the onFind will
be calling this function}
var
i: integer;
begin
{See comments for findforward}
{to find the word we go through the text on a character by character
basis but working backwards}
for i := finish downto start do
if TryAndMatch( Sender, i, start ) then
Exit;
end;
function TFindReplace.TryAndMatch( Sender: TFindDialog; index, finish: integer ): boolean;
{returns true if there was a match and false otherwise}
var
StringToTest: string;
StringComparison: TReplaceFunc;
{the function to use to compare 2 strings. Should be assigned
different values according to the search criteria}
FindTextLength: integer;
resourcestring
S_CANT_BE_FOUND = '%s could not be found';
begin
FindTextLength := Length( Sender.FindText );
{create a new string to test against}
StringToTest := copy( fEditor.Text, index+1, FindTextLength );
{assign a case sensitive or case insensitive string
comparison function to StringComparison depending
on the whether or not the user chose to match case.
The functions assigned are normal VCL functions.}
if frMatchCase in Sender.Options then
StringComparison := CompareStr
else
StringComparison := CompareText;
if (StringComparison( StringToTest, Sender.FindText ) = 0) and
TestWholeWord( Sender, copy( fEditor.Text, index, FindTextLength+2 ) ) then
{with TestWholeWord we pass the value index not index+1 so that it will also
get the previous character. We pass the value FindTextLenght+2 so it
will copy the next character after the test string aswell}
begin {if all true then we've found the text}
{highlight the word}
fEditor.SetFocus;
fEditor.SelStart := index;
fEditor.SelLength := FindTextLength;
{quit the function}
Result := true; {because we've found the word}
Exit;
end
{if we've tried the last character and we can't find it then
display a message saying so.}
else if (index = finish) and (FindActionOnEnd = frcAlertUser) then
ShowMessageFmt(S_CANT_BE_FOUND, [Sender.FindText])
{otherwise if the replace function requested us to keep quiet
about it then don't display the message to the user}
else if (index = finish) and (FindActionOnEnd = frcAlertReplace) then
FindActionOnEnd := frcEndReached;
Result := false; {didn't find it}
end;
procedure TFindReplace.DoFind(dialog: TFindDialog; direction: TFindDirection);
var
// highlightedText: pChar;
highlightedText: string;
begin
if direction = sdDefault then
begin
if frDown in dialog.Options then
direction := sdForwards
else
direction := sdBackwards;
end;
{check if there is already some highlighted text. If there is and
this text is the text to search for then it's probably been highlighted
by the previous find operation. In this case, move selStart to
the position after the final character so the find operation won't find
the same word again. If the user chose to search up then move selStart
to the character before the highlighted word}
if fEditor.SelLength > 0 then
begin
(*
GetMem( highlightedText, fEditor.SelLength + 1 );
fEditor.GetSelTextBuf( highlightedText, fEditor.SelLength+1 );
*)
highlightedText := fEditor.SelText;
{compare the two strings}
if StrIComp( PChar(highlightedText), pChar( dialog.FindText ) ) = 0 then
begin
if direction = sdForwards then
fEditor.selStart := fEditor.SelStart + fEditor.SelLength
else
fEditor.selStart := fEditor.SelStart - 1;
end;
(*
FreeMem( highlightedText, fEditor.SelLength + 1 );
*)
end;
{begin the search}
if direction = sdForwards then {the user choose to search down}
begin
{if the user has highlighted a block of text only search
within that block}
if fEditor.SelLength > 0 then
FindForwards( dialog, fEditor.selStart, fEditor.selStart + fEditor.selLength )
{otherwise search the whole of the text}
else
FindForwards( dialog, fEditor.selStart, fEditor.GetTextLen );
end
else {the user chose to search up}
begin
{if the user has highlighted a block of text only search
within that block}
if fEditor.SelLength > 0 then
FindBackwards( dialog, fEditor.selStart, fEditor.selStart + fEditor.selLength )
{otherwise search the whole of the text}
else
FindBackwards( dialog, 0, fEditor.selStart );
end;
end;
procedure TFindReplace.OnFind(Sender: TObject);
var
FindDialog: TFindDialog;
begin
FindDialog := Sender as TFindDialog;
DoFind(FindDialog, sdDefault);
end;
procedure TFindReplace.OnReplace( Sender: TObject );
var
ReplaceDialog: TReplaceDialog;
begin
ReplaceDialog := Sender as TReplaceDialog;
{set the action on end to alert the function not the user}
FindActionOnEnd := frcAlertReplace;
// TODO: UnDo does not work
{now replace the word}
if frReplace in ReplaceDialog.Options then
DoReplace(ReplaceDialog)
else
DoReplaceAll(ReplaceDialog);
{reset the action on end to alert the user}
FindActionOnEnd := frcAlertUser;
end;
procedure TFindReplace.DoReplace(dialog: TReplaceDialog);
begin
FindForwards( dialog, fEditor.selStart, fEditor.GetTextLen );
TryAndReplace(dialog);
FindForwards( dialog, fEditor.selStart, fEditor.GetTextLen ); // Jump to the next occurrence
end;
procedure TFindReplace.DoReplaceAll(dialog: TReplaceDialog);
begin
{see comments for DoReplace}
fEditor.BeginUpdate;
fEditor.BeginUndoBlock;
try
{if the user has highlighted a block of text only replace
within that block}
if fEditor.SelLength > 0 then
begin
// TODO: test this functionality
FindForwards( dialog, fEditor.selStart, fEditor.selStart + fEditor.selLength );
{keep replacing until we reach the end of the text}
while FindActionOnEnd <> frcEndReached do
begin
{we enclose the TryAndReplace in a loop because there might be more
than one occurence of the word in the line}
while TryAndReplace(dialog) do
FindForwards( dialog, fEditor.selStart, fEditor.selStart + fEditor.selLength );
FindForwards( dialog, fEditor.selStart, fEditor.selStart + fEditor.selLength );
end;
end
else {otherwise replace within the whole of the text}
begin
FindForwards( dialog, fEditor.selStart, fEditor.GetTextLen );
while FindActionOnEnd <> frcEndReached do
begin
while TryAndReplace(dialog) do
FindForwards( dialog, fEditor.selStart, fEditor.GetTextLen );
FindForwards( dialog, fEditor.selStart, fEditor.GetTextLen );
end;
end;
finally
fEditor.EndUpdate;
fEditor.EndUndoBlock;
end;
end;
function TFindReplace.TryAndReplace(dialog: TReplaceDialog): boolean;
{returns true if a replacement was made and false otherwise. This is
so a function can keep calling TryAndReplace until it returns false
since there might be more than one occurence of the word to replace
in the line}
var
LineNumber, ColumnNumber: integer;
OldSelStart: integer; {the position of the cursor prior to the text being replaced}
begin
{assume no replacement was made}
Result := false;
{check to see if the word was found otherwise we don't add the
replaceText to the editor. That is, only delete the selected text
and insert the replacement text if the end was not reached}
if not (FindActionOnEnd = frcEndReached) then
begin
{get the line number and column number of the cursor which
is needed for string manipulations later. We should do this
before the call to clear selection}
// TODO: only replace beginning at the selected section / caret, not from beginning of the line!!
LineNumber := fEditor.CaretY-1;
ColumnNumber := fEditor.CaretX-1;
{get the position of the cursor prior to the replace operation
so we cab restore it later}
OldSelStart := fEditor.SelStart;
// Note: "fEditor.ClearSelection" can be used to delete the selected text
// TODO: only replace beginning at the selected section / caret, not from beginning of the line
// TODO: support "whole word" ?
if frMatchCase in dialog.Options then
fEditor.Lines[LineNumber] := StringReplace(fEditor.Lines[LineNumber], dialog.FindText, dialog.ReplaceText, [])
else
fEditor.Lines[LineNumber] := StringReplace(fEditor.Lines[LineNumber], dialog.FindText, dialog.ReplaceText, [rfIgnoreCase]);
{set the result to true since we have made a replacement}
Result := true;
{reposition the cursor to the character after the last chracter in
the newly replacing text. This is mainly so we can locate multiple
occurences of the to-be-replaced text in the same line}
fEditor.SelStart := oldSelStart + length( dialog.ReplaceText );
end
end;
procedure TFindReplace.FindExecute;
begin
fFindDialog.Execute;
end;
procedure TFindReplace.ReplaceExecute;
begin
fReplaceDialog.Execute;
end;
function TFindReplace.TestWholeWord( Sender: TFindDialog; TestString: string ): boolean;
var
FindTextLength: integer;
begin
{assume it's not a whole word}
Result := false;
FindTextLength := Length( Sender.FindText );
{if the user didn't choose whole words only then basically
we don't care about it so return true}
if not (frWholeWord in Sender.Options) then
begin
Result := true;
Exit;
end;
{Test if the word is a whole word}
{Basically there are 4 cases: ( _ denotes whitespace )
1. _word_
2. \nword_
3. _word\n
4.\nword\n}
{case 1, note: #9 tab, #$A newline}
if (CharInSet(TestString[1], [' ', #9 ])) and (CharInSet(TestString[FindTextLength + 2], [' ', #9 ])) then
Result := true
{case 2}
else if(TestString[1] = #$A) and (CharInSet(TestString[FindTextLength + 2], [' ', #9 ])) then
Result := true
{case 3, note: #$D end of line}
else if(CharInSet(TestString[1], [' ', #9 ])) and (TestString[FindTextLength + 2] = #$D) then
Result := true
else if (TestString[1] = #$A) and (TestString[FindTextLength + 2] = #$D) then
Result := true
end;
procedure TFindReplace.FindContinue;
begin
if fFindDialog.FindText = '' then
begin
fFindDialog.Options := fFindDialog.Options + [frDown]; // Default direction: down
FindExecute;
end
else
DoFind(fFindDialog, sdDefault);
end;
procedure TFindReplace.FindNext;
begin
if fFindDialog.FindText = '' then
begin
fFindDialog.Options := fFindDialog.Options + [frDown];
FindExecute;
end
else
DoFind(fFindDialog, sdForwards);
end;
procedure TFindReplace.FindPrev;
begin
if fFindDialog.FindText = '' then
begin
fFindDialog.Options := fFindDialog.Options - [frDown];
FindExecute;
end
else
DoFind(fFindDialog, sdBackwards);
end;
procedure TFindReplace.GoToLine( LineNumber: integer );
var
currentLine: integer;
i: integer;
begin
{set the current line to 1}
currentLine := 1;
{go through the whole text looking for the line}
for i := 1 to fEditor.GetTextLen do
begin
if currentLine = LineNumber then
begin
{goto the position corresponding to the line}
fEditor.selStart := i;
fEditor.SetFocus;
{quit the function}
Exit;
end
else if fEditor.Text = #$D then
inc( currentLine );
end;
end;
procedure TFindReplace.CloseDialogs;
begin
fFindDialog.CloseDialog;
fReplaceDialog.CloseDialog;
end;
(*
procedure Register;
begin
RegisterComponents('Tek-tips', [TFindReplace]);
end;
*)
end.