Function Format compatible with UTF8

[esvignolo]

Hello, I was trying to use the format function, but with the utf8 strings I have problems, as I could see, it has to do with the length of utf8 strings.
Anyone know if there is a replacement of this function for utf.

Code: Pascal  [Select][+][-]

1.    sText:='Impresión Color';
2.    sText:=Format('%-40s',[sText]); //the result have 39 characters
3.    sText:='Impresion Color';
4.    sText:=Format('%-40s',[sText]); //the result have 40 characters
5.  

Thanks!

[Ñuño_Martínez]

It should be the other way:  the string with the acute has one more CHAR than the oter one because such UTF-8 character is 16 bit wide.

I've used Format with UTF-8 strings and never had that problem.
_________________________________________________

Debería ser al revés:  la cadena con el acento tiene un CHAR más que la que no lo tiene ya que el carácter UTF-8 correspondiente es de 16 bits.

Yo he usado Format con cadenas UTF-8 a menudo y no he visto nunca este problema.

[esvignolo]

Hi Ñuño, the problem maybe is the length:

http://forum.lazarus.freepascal.org/index.php/topic,36097.0.html

The format work, but when u use a accent word, in string lose one char.

[Ñuño_Martínez]

If you read the thread you linked, it demonstrates my point.

Length counts bytes, no characters!  You should use the appropriate character counter function to do that (as UTF8Length for UTF-8 strings).

And as I've said, Format works properly with UTF-8 strings so what's the problem?

[esvignolo]

Hi!, thanks for answer. The length problem make the generation of spaces to complete the length has a fail.

I make a app sample and a screenshot.

Code: Pascal  [Select][+][-]

1. unit Unit1;
2.  
3. {$mode objfpc}{$H+}
4.  
5. interface
6.  
7. uses
8.   Classes, SysUtils, FileUtil, Forms, Controls, Graphics, Dialogs, StdCtrls;
9.  
10. type
11.  
12.   { TForm1 }
13.  
14.   TForm1 = class(TForm)
15.     Button1: TButton;
16.     Edit1: TEdit;
17.     Memo1: TMemo;
18.     procedure Button1Click(Sender: TObject);
19.   private
20.  
21.   public
22.  
23.   end;
24.  
25. var
26.   Form1: TForm1;
27.  
28. implementation
29.  
30. {$R *.lfm}
31.  
32. { TForm1 }
33.  
34. procedure TForm1.Button1Click(Sender: TObject);
35. var sText:string;
36. begin
37.   sText:=Format('%-40s<-length=40',[Edit1.Text]);
38.   Memo1.Lines.Add(sText);
39.  
40. end;
41.  
42. end.
43.  
44.  

[wp]

Use UTF8Length() to count the characters, not the bytes, of a utf8 string. It is in unit LazUTF8 where you find also other useful procedures and functions (e.g. UTF8PadRight(txt, count) - to add spaces to the right of the string txt such that the total character length is count).

If you absolutely want to use the Format function you cannot use a fixed width parameter in the format string, instead use a '*', calculate the required width parameter to compensate for the difference in byte and character count and pass it as an additional parameter to the parameter list - not very nice...

Code: Pascal  [Select][+][-]

1. sText := Format('%-*s<length=40', [40 - UTF8Length(Edit1.Text) + Length(Edit1.Text), Edit1.Text1]);

[esvignolo]

Thanks wp!, i use a similar solution, using UTF8PadRight, but I like how you solved with the length parameter in format function. It is a shame that this function does not work with UTF because it is quite flexible, since it formats several types of data and supports alignment.