TCanvas.TextWidth Method

Returns the width, in pixels, of a string rendered in the current font.

Pascal

function TextWidth(const Text: string): Integer;

C++

__fastcall int TextWidth(const AnsiString Text);

Description

Use TextWidth to determine the length a string will occupy in the image. TextWidth indicates whether a given string will fit in the available space. Other graphical elements in the image such as lines, or additional strings can be positioned to accommodate the width of the text.

TextWidth returns the same value as TextExtent(Text).cx.

C++ Examples:

Copy Code

/*
This project requires a TPageControl and several TTabPages.
To add new pages, right-click the TPageControl and select 
New Page.  During the form creation the width and height of 
all tabs on the Page Control becomes double the largest 
previous value. So if there are three tabs with captions that
are 12, 23, and 19 characters long, the TabWidth would be the
number of pixels required to fit 46 characters.
*/
void __fastcall TForm1::FormCreate(TObject *Sender)
{
  for (int i = 0; i < PageControl1->PageCount; i++)
  {
     AnsiString s = PageControl1->Pages[i]->Caption;
     if (Canvas->TextWidth(s) * 2 > PageControl1->TabWidth)
        PageControl1->TabWidth = Canvas->TextWidth(s) * 2;
      if (Canvas->TextHeight(s) * 2 > PageControl1->TabHeight)
        PageControl1->TabHeight = Canvas->TextHeight(s) * 2;
  }
}

Delphi Examples:

Copy Code

{
This project requires a TPageControl and several TTabPages.
To add new pages, right-click the TPageControl and select 
New Page.  During the form creation the width and height of 
all tabs on the Page Control becomes double the largest 
previous value. So if there are three tabs with captions that
are 12, 23, and 19 characters long, the TabWidth would be the
number of pixels required to fit 46 characters.
} 
procedure TForm1.FormCreate(Sender: TObject);
var
  i: Integer;
begin
  with PageControl1 do
  begin
    for i := 0 to PageCount - 1 do
    begin
      if (Canvas.TextWidth(Pages[i].Caption) * 2) > TabWidth then
        TabWidth := Canvas.TextWidth(Pages[i].Caption) * 2;
      if (Canvas.TextHeight(Pages[i].Caption) * 2) > TabHeight then
        TabHeight := Canvas.TextHeight(Pages[i].Caption) * 2;
    end;
  end;
end;