How to do this find and replace?

Question

I have been trying to figure out the regex for this find and replace (I thought it would be easy!), but my frustration is getting the better of me and any help would be greatly appreciated.  I'm trying to do two find and replaces:
1) In the first, I'd like to find:
</script>
XXXX
</head>
where XXXX are always four letters (uppercase) and I want to store the four letters as a variable ($1) to use in the replace
I'd like to replace this with a bunch of javascript and in the middle of the script, I'd place the variable referencing these four letters (<script type="text/javascript">var blah = new Spry.Data.XMLDataSet("http://$1.com"blahblah</script></head>
2) The second find is similar:
</html>
XXXXXXXX
where once again X are 8 letters in uppercase following the close of the html tag (this has resulted from previous find and replaces and now I'm trying to correct things)
I simply want to delete these letters in this case (so will leave the replace blank).
Any help is greatly appreciated!  Thank you

Answer 1

Having 46 people view a post without replying is not unusual. Some people look at a question to see if it's something they'd like to know the answer to, and then come back  when it has eventually been answered.
I'm not sure if you need to escape forward slashes in Dreamweaver's Find and Replace dialog box, but I normally do because both JavaScript and PHP normally use forward slashes as delimiters to mark the beginning and end of the regex like this:
var pattern = /[A-Z]{4}/; // JavaScript
$pattern = '/[A-Z]{4}/';   // PHP
When a forward slash appears inside the regex, you need to escape it with a backslash to avoid confusion with the closing delimiter.
As you have worked out, a capturing group is created by wrapping part of the regex in parentheses.
If you want to match exactly 38 characters, you can use [\S\s]{38}. That includes spaces, newline characters, symbols, everything.
If you're trying to find everything between two tags, you can do this:
(<\/tag_name>)([^<]+)
The closing tag is captured as $1 and everything up to the next opening tag is captured as $2.
Learning regular expressions is not easy. I don't claim to be an expert, but I enjoy the challenge of trying to solve them. If you're interested in regular expressions, there are several books published by O'Reilly. "Mastering Regular Expressions" is the ultimate authority, but it's a difficult read (not because it's badly written, but because of the complexity of the subject). "Regular Expressions Cookbook" is very good. There's also a new "Introducing Regular Expressions", but I haven't read it.