Count number of words in a text file

The same as a function:

procedure TForm1.Button1Click(Sender: TObject);  
begin
   ShowMessage(IntToStr(CountFileWords('C:\Test.txt')));
end;


function CountFileWords(FName:String):Integer;
var
SL:TStringList;
i,j:Integer;
s:String;
begin
   Result:=0;
   SL:=TStringList.create;
   try
     SL.LoadFromFile('C:\Test.txt');
     for i:=0 to SL.Count-1 do begin
       s:=Trim(SL[i]);
       if Length(s)>0 then
         for j:=1 to Length(s) do
           if (((s[j]<>' ') and (j=1)) or ((s[j]<>' ')and(s[j-1]=' '))) then
             inc(Result);
   end;
   finally
     SL.Free;
   end;
end;

Oops, in the case of the function it should of course be:

  SL.LoadFromFile(FName);

instead of

 SL.LoadFromFile('C:\Test.txt');

To exclude non-word stand alone chars, the function could be expanded like this
(any char can be added to "NotValid")

function CountFileWords(FName:String):Integer;
var
SL:TStringList;
i,j:Integer;
s:String;
var NotValid : set of Char;
begin
   Result:=0;
   NotValid:= ['.',',','-','_','|','<','>'];
   SL:=TStringList.create;
   try
     SL.LoadFromFile(FName);
     for i:=0 to SL.Count-1 do begin
       s:=Trim(SL[i]);
       if Length(s)>0 then
         for j:=1 to Length(s) do
           if (((s[j]<>' ') and (j=1)) or ((s[j]<>' ') and ((s[j-1]=' ') or (s[j-1] in NotValid)))
               and (not(s[j] in NotValid))) then
             inc(Result);
     end;
   finally
     SL.Free;
   end;
end;

An exact definition of what a word is can help decide which method is best (e.g use ['a'..'z','A'..'Z']...)