How do I count characters in a string, excluding certain types?

Question

I need to determine the total number of characters in a textbox and display the value in a label, but all whitespace need to be excluded.

Here is the code:

var     
sLength : string;
i : integer;
begin
     sLength := edtTheText.Text;
     slength:= ' ';
     i := length(sLength);

     //display the length of the string
     lblLength.Caption := 'The string is ' +  IntToStr(i)  + ' characters long';

Answer 1

You can count the non-white space characters like this:

uses
  Character;

function NonWhiteSpaceCharacterCount(const str: string): Integer;
var
  c: Char;
begin
  Result := 0;
  for c in str do
    if not Character.IsWhiteSpace(c) then
      inc(Result);
end;

This uses Character.IsWhiteSpace to determine whether or not a character is whitespace. IsWhiteSpace returns True if and only if the character is classified as being whitespace, according to the Unicode specification. So, tab characters count as whitespace.