CODEWITHSUNDEEP
delphiword-wrapdrawtext
XBasic3000
XBasic3000

Reputation: 3486

How can I get the new height of a wrapedtext of DrawText();?

code sample

procedure TForm1.Button1Click(Sender: TObject);
var
  r: Trect;
  s: String;
begin
  R := Rect(0,0, 300, 100);
  s := 'WordWrapTextOut(TargetCanvas: TCanvas; var x, y: integer; S: string; maxwidth, lineheight: integer);';
  DrawText(Canvas.Handle, PChar(s),  length(s), R, DT_WORDBREAK or DT_LEFT);
end;

I want to wrap the text in 300px width but how can I get the new Height? Is there a way or any solution?

Upvotes: 2

Views: 2637

Answers (3)

user532231
user532231

Reputation:

As was mentioned here you can get it by calling DrawText function with DT_CALCRECT flag specified what actually won't paint anything; it just calculates appropriate rectangle and returns it to variable R.

procedure TForm1.Button1Click(Sender: TObject);
var
  R: TRect;
  S: String;
begin
  R := Rect(0, 0, 20, 20);
  S := 'What might be the new high of this text ?';
  DrawText(Canvas.Handle, PChar(S), Length(S), R, DT_WORDBREAK or DT_LEFT or DT_CALCRECT);
  ShowMessage('New height might be '+IntToStr(R.Bottom - R.Top)+' px');
end;

What means if you call it twice using the following example, you'll get drawn the wrapped text. It's because the first call with DT_CALCRECT calculates the rectangle (and modify R variable by doing it) and the second call draws the text in that modified rectangle area.

procedure TForm1.Button1Click(Sender: TObject);
var
  R: TRect;
  S: String;
begin
  R := Rect(0, 0, 20, 20);
  S := 'Some text which will be stoutly wrapped and painted :)';
  DrawText(Canvas.Handle, PChar(S), Length(S), R, DT_WORDBREAK or DT_LEFT or DT_CALCRECT);
  DrawText(Canvas.Handle, PChar(S), Length(S), R, DT_WORDBREAK or DT_LEFT);
end;

Upvotes: 2

PetriW
PetriW

Reputation: 1245

If you want to update your rectangle before drawing the text you could use DT_CALCRECT. DrawText will then modify your rectangle to the new height (and width if necessary). If you only need the height though use the return value as Andreas Rejbrand showed.

Here's a sample of this:

procedure TForm1.Button1Click(Sender: TObject);
var
  r: Trect;
  s: String;
begin
  R := Rect(0,0, 300, 100);
  s := 'WordWrapTextOut(TargetCanvas: TCanvas; var x, y: integer; S: string; maxwidth, lineheight: integer);';
  if DrawText(Canvas.Handle, PChar(s),  length(s), R, DT_CALCRECT or DT_WORDBREAK or DT_LEFT) <> 0 then
  begin
    DrawText(Canvas.Handle, PChar(s),  length(s), R, DT_WORDBREAK or DT_LEFT);
    r.Top := r.Bottom;
    r.Bottom := r.Bottom * 2;
    DrawText(Canvas.Handle, PChar(s),  length(s), R, DT_WORDBREAK or DT_LEFT);
  end;
end;

I would recommend reading the docs for more details: http://msdn.microsoft.com/en-us/library/dd162498(v=vs.85).aspx

Upvotes: 2

Andreas Rejbrand
Andreas Rejbrand

Reputation: 108963

The height of the drawn text is the returned value of DrawText.

HeightOfText := DrawText(...

Upvotes: 4

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