Author: William Gerbert

Parsing Strings using TParser

Answer:

Delphi has a cool class called TParser that the IDE uses to parse the source code. 
You can also use it to parse strings.

This function takes a string argument and splits it into separate words for you.

1   procedure ParseThis(MyStr: string);
2   var
3     MyParser: TParser;
4     MS: TMemoryStream;
5   begin
6     MS := TMemoryStream.Create;
7     MS.Position := 0;
8     MS.write(MyStr[1], Length(MyStr));
9     MS.Position := 0;
10    MyParser := TParser.Create(MS);
11    MyStr := MyParser.TokenString;
12    ShowMessage(MyStr);
13    while MyParser.Token <> toEOF do
14    begin
15      MyParser.NextToken;
16      if MyParser.TokenSymbolIs(MyParser.TokenString) then
17      begin
18        MyStr := MyParser.TokenString;
19        ShowMessage(MyStr);
20      end;
21    end;
22    MyParser.Free;
23    MS.Free;
24  end;
25  
26  procedure TForm1.Button1Click(Sender: TObject);
27  begin
28    ParseThis('Now is the time for all men to come to the aid of their country.');
29  end;