Title: How to get a range of text from a RichEdit
Question: Sometimes while using RichEdit you need to get just part of the text
from that control, without setting a selection and using the SelText property.
The code shows the way to do that.
Answer:
{overrides wrong TTextRange definition in RichEdit.pas}
TTextRange = record
chrg: TCharRange;
lpstrText: PAnsiChar;
end;
function REGetTextRange(RichEdit: TRichEdit;
BeginPos, MaxLength: Integer): string;
{RichEdit - RichEdit control
BeginPos - absolute index of first char
MaxLength - maximum chars to retrieve}
var
TextRange: TTextRange;
begin
if MaxLength0 then
begin
SetLength(Result, MaxLength);
with TextRange do
begin
chrg.cpMin := BeginPos;
chrg.cpMax := BeginPos+MaxLength;
lpstrText := PChar(Result);
end;
SetLength(Result, SendMessage(RichEdit.Handle, EM_GETTEXTRANGE, 0,
longint(@TextRange)));
end
else Result:='';
end;
This function can be used to extract a word under the current mouse pointer
position:
function RECharIndexByPos(RichEdit: TRichEdit; X, Y: Integer): Integer;
{ function returns absolute character position for given cursor coordinates}
var
P: TPoint;
begin
P := Point(X, Y);
Result := SendMessage(RichEdit.Handle, EM_CHARFROMPOS, 0, longint(@P));
end;
function REExtractWordFromPos(RichEdit: TRichEdit; X, Y: Integer):=
string;
{ X, Y - point coordinates in rich edit control }
{returns word , under current cursor position}
var
BegPos, EndPos: Integer;
begin
BegPos := RECharIndexByPos(RichEdit, X, Y);
if (BegPos (SendMessage(RichEdit.Handle,EM_FINDWORDBREAK,WB_CLASSIFY,BegPos) and
(WBF_BREAKLINE or WBF_ISWHITE) 0 ) then
begin
result:='';
exit;
end;
if SendMessage(RichEdit.Handle, EM_FINDWORDBREAK,WB_CLASSIFY,BegPos-1) and
(WBF_BREAKLINE or WBF_ISWHITE) = 0 then
BegPos:=SendMessage(RichEdit.Handle, EM_FINDWORDBREAK,
WB_MOVEWORDLEFT, BegPos);
EndPos:=SendMessage(RichEdit.Handle,EM_FINDWORDBREAK,WB_MOVEWORDRIGHT,BegPos);
Result:=TrimRight(REGetTextRange(RichEdit, BegPos, EndPos - BegPos));
end;