regular expression for a word

Question

I am doing a string parsing problem in PHP. I want a regular expression for a word in a dictionary. The word can contain only A-Z and a-z. I came up with this regex but this seems to be not working. Can someone help.

$regexp = "/[A-z]+/";
if(preg_match($regexp,$buffer)){    
   print $buffer . "<BR>";
}

Adding rkt's comment for eadibility

currently using this regex

$regexp = "/[A-Za-z]+/";

but still lot of irrelevant words are getting printed , for eg .

a.new,#quickbar a.new{color:#ba0000} enwiki:resourceloader:filter:minify-css:5:f2a9127573a22335c2a9102b208c73e7 wgNamespaceNumber=0;
wgAction="view";
wgPageName="Roger_Federer";
wgMainPageTitle="‌​Main Page";
wgWikimediaMobileUrl="http:\/\/en.m.wikipedia.org\/wiki";
document.writeln("\x3cdiv id=\"localNotice\"\x3e\x3cp\x3e\x3c/p\x3e\n\x3c/div\x3e");

Answer 1

If you want to match a whole word only...

/\b[A-Z]+\b/i

Answer 2

Besides the problem that Limo Wan Kenobi noted, your regex doesn't do what you think it does.

/[A-Za-z]+/

All this checks is that a letter, either case, appears somewhere in the input. If your input looks like this:

1111112222222333333333A333333444444555555567

It will still match.

What you are looking for is this regular expression:

/^[A-Za-z]+$/

This will match the beginning of the string, then one or more letters, and finally the end of the string. Now, there's no room for anything except letters!