Regular Expressions

A regular expression is a search string that uses special characters to match patterns of text. The pattern must be a full match, not a partial match.

A simplified subset of regular expression syntax is shown below.

Character	Description	Find	Matches
.	Any single character	a.e	ave, ale, ate, etc.
*	Zero or more occurrences of the preceding characters	a*b	b, ab, aaab, etc.
+	One or more occurrences of the preceding characters	a+b	ab, aaab, etc.
?	Zero or one occurrence of the preceding characters	ca?b	cb, cab, etc.
{n}, {n,m}	A single character can be repeated a specific number of times: a{n}  Matches 'a' repeated exactly n times a{n,}  Matches 'a' repeated n or more times a{n, m}  Matches 'a' repeated between n and m times inclusive	a{2,3}	aa, aaa
|	Matches either of its arguments. Parenthesis can be used:	abc|def ab(d|ef)	abc, def abd, abef
[] ^	Defines a set or range and matches any members of the set or range: ^ will match any character that is NOT in the specified set or range:	[abc] [a-d] [^a-d]	a, b, c a, b, c, d e, f, g, etc.

The following link also has more detailed information on Regular Expressions: http://msdn.microsoft.com/en-us/library/az24scfc.aspx