Editing and formatting

Text selection

Inline example 1PascalC++

// Select all
RichEditor1.SelectAll;

// Select a range (character offset, length)
RichEditor1.Select(10, 5);

// Deselect
RichEditor1.ClearSelection;

// Select all
RichEditor1->SelectAll;

// Select a range (character offset, length)
RichEditor1->Select(10, 5);

// Deselect
RichEditor1->ClearSelection;

Character formatting

Apply formatting to the current selection or the cursor position (affects new typing):

Method	Description
`SetSelectionBold(Boolean)`	Bold text
`SetSelectionItalic(Boolean)`	Italic text
`SetSelectionUnderline(Boolean)`	Underline
`SetSelectionStrikeOut(Boolean)`	Strikethrough
`SetSelectionSuperscript(Boolean)`	Superscript
`SetSelectionSubscript(Boolean)`	Subscript
`SetSelectionFontName(string)`	Font family
`SetSelectionFontSize(Integer)`	Font size in points
`SetSelectionColor(TTMSFNCGraphicsColor)`	Text color

Inline example 2PascalC++

// Make selected text bold and red
RichEditor1.SetSelectionBold(True);
RichEditor1.SetSelectionColor(gcRed);

// Make selected text bold and red
RichEditor1->SetSelectionBold(true);
RichEditor1->SetSelectionColor(gcRed);

Reading the same properties returns the formatting at the cursor or in the selection.

Paragraph formatting

Alignment is applied through SetSelectionAttribute with a TAlignment value (taLeftJustify, taCenter, taRightJustify). LineSpacing is an Integer property (default 0) that adds spacing between lines.

Inline example 3PascalC++

RichEditor1.SetSelectionAttribute(taCenter);

RichEditor1->SetSelectionAttribute(taCenter);

Lists

SetSelectionBullets applies a bullet or number style to the selected lines, and toggles it off when the caret is already in a list of the same type. Use RemoveSelectionBullets to clear it explicitly.

Inline example 4PascalC++

// Numbered list: btNumber; bulleted list: btCircle, btSquare, btArrow, btTick, btStar
RichEditor1.SetSelectionBullets(btNumber);
RichEditor1.SetSelectionBullets(btCircle);
RichEditor1.RemoveSelectionBullets;

// Numbered list: btNumber; bulleted list: btCircle, btSquare, btArrow, btTick, btStar
RichEditor1->SetSelectionBullets(btNumber);
RichEditor1->SetSelectionBullets(btCircle);
RichEditor1->RemoveSelectionBullets;

Indentation

Inline example 5PascalC++

RichEditor1.SetSelectionIndent(24);   // left indent of the selected paragraphs
RichEditor1.SetSelectionIndent(0);    // remove the indent

RichEditor1->SetSelectionIndent(24);   // left indent of the selected paragraphs
RichEditor1->SetSelectionIndent(0);    // remove the indent

Undo and redo

Inline example 6PascalC++

if RichEditor1.CanUndo then RichEditor1.Undo;
if RichEditor1.CanRedo then RichEditor1.Redo;

if (RichEditor1->CanUndo) RichEditor1->Undo;
if (RichEditor1->CanRedo) RichEditor1->Redo;

Inserting text

Inline example 7PascalC++

// Insert at cursor position
RichEditor1.InsertText('Hello, world!');

// Insert at cursor position
RichEditor1->InsertText("Hello, world!");

Reading content

Inline example 8PascalC++

// Plain text
var plain := RichEditor1.PlainText;

// HTML
var html := RichEditor1.HTML;

// Plain text
var plain = RichEditor1->PlainText;

// HTML
var html = RichEditor1->HTML;

Clipboard: cut, copy, and paste

The editor exchanges more than plain text with the clipboard: a copy carries the selection as an internal rich-text stream, as RTF, and as plain text at the same time, so a paste back into the editor keeps its formatting while a paste into a plain-text field still works. Reach for the clipboard events when the document must not accept everything a user might paste - stripping tabs out of spreadsheet text, or refusing a multi-megabyte screenshot.

Member	Purpose
`CopyToClipboard`	Copies the selection in every format the editor produces.
`CutToClipboard`	Copies the selection, then deletes it. A selected image is copied as a picture.
`PasteFromClipboard`	Pastes the clipboard content over the selection. Returns the plain text that was inserted.
`ClipboardHasContent`	`True` when the clipboard holds a format the editor can paste - use it to enable a Paste command.
`ClipboardFormats`	The `TClipboardFormat` set (`cfRTE`, `cfRTF`, `cfText`, `cfHTML`, `cfBMP`, `cfFile`) the editor is willing to accept.
`CopyRTFToClipboard`, `CopyHTMLToClipboard`	Place only the RTF or only the HTML representation on the clipboard.

Event	Signature
`OnPasteText`	`(Sender: TObject; var AText: string; var Allow: boolean)`
`OnPasteBitmap`	`(Sender: TObject; ABitmap: TTMSFNCBitmap; var Allow: boolean)`
`OnPasteFormattedText`	`(Sender: TObject; AStream: TStream)`

Filtering and restricting clipboard operationsPascalC++

procedure TForm1.RichEditorPasteText(Sender: TObject; var AText: string;
  var Allow: boolean);
begin
  // AText is a var parameter, so rewriting it here changes what is inserted.
  AText := StringReplace(AText, #9, ' ', [rfReplaceAll]);
  Allow := Trim(AText) <> '';
end;

procedure TForm1.RichEditorPasteBitmap(Sender: TObject;
  ABitmap: TTMSFNCBitmap; var Allow: boolean);
begin
  // Keep an oversized screenshot out of the document rather than scaling it
  // after the fact.
  Allow := (ABitmap.Width <= 1600) and (ABitmap.Height <= 1600);
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
  TMSFNCRichEditor1.OnPasteText := RichEditorPasteText;
  TMSFNCRichEditor1.OnPasteBitmap := RichEditorPasteBitmap;

  // Accept rich text and plain text on paste, but never a bitmap.
  TMSFNCRichEditor1.ClipboardFormats := [cfRTF, cfText];
end;

procedure TForm1.PasteButtonClick(Sender: TObject);
var
  s: string;
begin
  // Use ClipboardHasContent to drive the enabled state of a Paste command;
  // it reports whether any pastable format is present at all.
  if not TMSFNCRichEditor1.ClipboardHasContent then
    Exit;

  // The result is the plain text that was inserted. It is empty when the
  // clipboard delivered rich text or a bitmap instead.
  s := TMSFNCRichEditor1.PasteFromClipboard;
  StatusLabel.Text := Format('Pasted %d characters of plain text', [Length(s)]);
end;

procedure TForm1.CopyButtonClick(Sender: TObject);
begin
  if TMSFNCRichEditor1.HasSelection then
    TMSFNCRichEditor1.CopyToClipboard
  else
    TMSFNCRichEditor1.SelectAll;
end;

procedure TForm1.CutButtonClick(Sender: TObject);
begin
  if TMSFNCRichEditor1.HasSelection then
    TMSFNCRichEditor1.CutToClipboard;
end;

void __fastcall TForm1::RichEditorPasteText(TObject *Sender, System::UnicodeString &AText,
  bool &Allow)
{
  // AText is a var parameter, so rewriting it here changes what is inserted.
  AText = StringReplace(AText, "\t", " ", TReplaceFlags() << rfReplaceAll);
  Allow = Trim(AText) != "";
}

void __fastcall TForm1::RichEditorPasteBitmap(TObject *Sender,
  TTMSFNCBitmap *ABitmap, bool &Allow)
{
  // Keep an oversized screenshot out of the document rather than scaling it
  // after the fact.
  Allow = (ABitmap->Width <= 1600) && (ABitmap->Height <= 1600);
}

void __fastcall TForm1::FormCreate(TObject *Sender)
{
  TMSFNCRichEditor1->OnPasteText = RichEditorPasteText;
  TMSFNCRichEditor1->OnPasteBitmap = RichEditorPasteBitmap;

  // Accept rich text and plain text on paste, but never a bitmap.
  TMSFNCRichEditor1->ClipboardFormats = TClipboardFormats() << TClipboardFormat::cfRTF << TClipboardFormat::cfText;
}

void __fastcall TForm1::PasteButtonClick(TObject *Sender)
{
  // Use ClipboardHasContent to drive the enabled state of a Paste command;
  // it reports whether any pastable format is present at all.
  if (!TMSFNCRichEditor1->ClipboardHasContent())
    return;

  // The result is the plain text that was inserted. It is empty when the
  // clipboard delivered rich text or a bitmap instead.
  System::UnicodeString s = TMSFNCRichEditor1->PasteFromClipboard();
  StatusLabel->Text = Format("Pasted %d characters of plain text", ARRAYOFCONST((s.Length())));
}

void __fastcall TForm1::CopyButtonClick(TObject *Sender)
{
  if (TMSFNCRichEditor1->HasSelection())
    TMSFNCRichEditor1->CopyToClipboard();
  else
    TMSFNCRichEditor1->SelectAll();
}

void __fastcall TForm1::CutButtonClick(TObject *Sender)
{
  if (TMSFNCRichEditor1->HasSelection())
    TMSFNCRichEditor1->CutToClipboard();
}

Paste order and pitfalls

PasteFromClipboard walks the available formats in a fixed order - rich-text stream, then RTF, then bitmap, then plain text - and inserts the first match in each group it is allowed to use. Four consequences are worth knowing:

Rich text wins over plain text. The plain-text branch is skipped once a rich-text or RTF paste succeeded, so OnPasteText does not fire for a formatted paste. A sanitiser that only lives in OnPasteText is bypassed by any clipboard that also carries RTF; remove cfRTF from ClipboardFormats if plain text must always be the route in.
A bitmap is not mutually exclusive. The bitmap branch is not skipped by a preceding rich-text paste, so a clipboard holding both RTF and an image can insert both in one call.
The return value only reflects the plain-text branch. It is an empty string after a formatted or bitmap paste, which is not an error.
On FMX targets ClipboardFormats gates pasting only. A copy always publishes plain text, RTF, and (except on Android) the internal rich-text stream regardless of the set, so narrowing ClipboardFormats does not reduce what other applications see when they paste from your document.

Combining programmatic editing, formatting, and content retrieval

Build a formatted report programmaticallyPascalC++

procedure TForm1.BuildReport;
var
  Html: string;
begin
  RichEditor1.Clear;

  // Centered bold heading
  RichEditor1.AddText('Project Report', 18, 'Arial', [TFontStyle.fsBold], taCenter);
  RichEditor1.AddLineBreak;

  // Left-aligned paragraph
  RichEditor1.AddText('This report summarizes the work completed in Q2.', 12, 'Arial', [], taLeftJustify);

  // Bulleted list: AddBullet starts a new line and adds the bullet marker
  RichEditor1.AddBullet(btCircle);
  RichEditor1.AddText('Feature A completed');
  RichEditor1.AddBullet(btCircle);
  RichEditor1.AddText('Feature B in progress');

  // Retrieve the result as HTML
  Html := RichEditor1.ContentAsHTML;
end;

void __fastcall TForm1::BuildReport()
{
  System::UnicodeString Html;
  RichEditor1->Clear();

  // Centered bold heading
  RichEditor1->AddText("Project Report", 18, "Arial", TFontStyles() << TFontStyle::fsBold, taCenter);
  RichEditor1->AddLineBreak();

  // Left-aligned paragraph
  RichEditor1->AddText("This report summarizes the work completed in Q2.", 12, "Arial", TFontStyles(), taLeftJustify);

  // Bulleted list: AddBullet starts a new line and adds the bullet marker
  RichEditor1->AddBullet(Fmx::Tmsfncricheditorbase::btCircle);
  RichEditor1->AddText("Feature A completed");
  RichEditor1->AddBullet(Fmx::Tmsfncricheditorbase::btCircle);
  RichEditor1->AddText("Feature B in progress");

  // Retrieve the result as HTML
  Html = RichEditor1->ContentAsHTML();
}

Rich editor document with a bold heading, a paragraph with coloured, bold and italic runs, a bulleted list, and a selected word

TTMSFNCRichEditor — SetSelectionBold, SetSelectionItalic, SetSelectionUnderline, SetSelectionFontName, SetSelectionFontSize, SetSelectionColor, InsertText, SelectAll, Undo, Redo