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If first line of memo starts with either http:// or www. do something?

Hi folks,

The title is quite selfexplanatory but nonetheless, I have this application which extracts certain portions of text between certain tags I fill memo1 with sourcode after which a button press filles memo2 with all the text portions that occur between two defined tags.

Now after this is done I want the app to count the number of links. This is only useful when it contains the links.

I\m planning on using the onChange event but dont know how to code this yet.

Thanks in advance,

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3 Solutions
Can you use Pos such as:

of (pos('http://', memo1.lines[0] > 0) or (pos('www', memo1.lines[0] > 0)  then
 ...// do something

This checks just your first line only.

Do a for loop to check other lines.

Hope this helped.

Again, my keyboard cannot type!

the 'of' is supposed t o be IF.

if (pos.....

Some things you should be aware of is that the Pos function is case sensetive, so while it would detect 'http://' or 'www' in the example above, it would not detect 'HTTP://' or 'WWW'. If you don't want the Pos to be case sensetive, then you would have to convert both strings to capitals using the function UpperCase (one way to do it), e.g. Pos('HTTP://', UpperCase(Memo1.Lines[i]));

Another thing is that the Pos function returns the position of a substring in a string, which means that in the example above, it will detect 'http://' or 'www' in any locations of the strings, so the string ' abc 123 www ' would result in a match as well. If you only want to detect if the string starts with 'http://' or 'www', then you should test that it returns the first position, as in this line "Pos('http://', memo1.lines[i]) = 1". However there are easier ways to do this test.

If you want to test if the string only starts with a text, then you could use AnsiStartsText which exists in the StrUtils unit (in later versions of delphi the function StartsText also exist). The function AnsiStartsText is case insensetive, which means that it would detect 'www' as well as 'WWW'. Also if you want to ignore any white spaces in the start of the text, before you do your string match, then you could use the TrimLeft function on all the lines you test (TrimLeft removes all the whitespace characters in the start of the string), e.g. the reason to use TrimLeft is to detect 'www' as well as '   www' but not 'abc www'.

The example below uses a Memo and a Label on a Form. connect the Memo1Change event to run.

procedure TForm1.Memo1Change(Sender: TObject);
var i, j : Integer;
  j := 0;
  for i := 0 to memo1.Lines.Count-1 do
    if (AnsiStartsText('http://', TrimLeft(memo1.lines[i])) or AnsiStartsText('www', TrimLeft(memo1.lines[i])))
      then inc(j); // Do your stuff...
  label1.Caption := IntToStr(j);

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PeterdeBAuthor Commented:
Many thanks!

@ Johnjces > your comment would do
@ Hypo > yours is more accurate and complete

That's why I split the points :)


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