Regular Expressions
Updated: May 13, 2016
Applies To: System Center 2012 SP1 - Orchestrator, System Center 2012 - Orchestrator, System Center 2012 R2 Orchestrator
In System Center 2012 - Orchestrator, regular expressions let you match a string to a pattern. The regular expression can contain a number of different elements that define the pattern. Smart Link Properties use regular expressions to perform pattern matching.
Advanced Regular Expressions
To build regular expressions, you must create an expression that contains the text that you are searching for and special characters that create a pattern, which describes how the text that you are searching for appears.
| Character | Meaning |
|---|---|
| . | Matches any character except a newline. |
| * | Matches the preceding item 0 or more times. For example, the "a*" pattern matches any string of a's in a row "a", "aaa", "aaaaaaaaaaaa", and an empty string "". To match any string of any character, use a dot followed by an asterisk. For example "a.*" matches any text that begins with the letter "a" and ends with any string of characters such as "abbb", "abcdef", or "automatic restart". |
| + | Matches the preceding item 1 or more times. This is like * but you must have a least 1 of the preceding item to make a match. For example, the "ab+" pattern matches "abbbbb", "ab", but does not match "a". To contrast, the "ab*" pattern matches "a". |
| ? | Matches the preceding item 0 or 1 time. For example, the "ab?" pattern matches "a" or "ab" but does not match "abbb". |
| | | Matches either the preceding expression or the following expression. Logical OR operator. |
| $ | Matches the expression at the end of the input or line. For example, "ab$" matches "I took a cab" or "drab" but does not match "absolutely not". |
| ^ | Matches the expression at the beginning of the input or line. For example, "^ab" matches "absolutely not" or "abacuses are great!" but does not match "I took a cab" or "drab". |
| \ | For characters that are usually treated as special. This indicates that the next character is literal and is not to be treated as a special character. For example, "\." means match the "." character and not just any character. |
| [ ] | A character set. Matches any one of the enclosed characters. You can specify a range of characters by using a hyphen. For example, [a-zA-Z] matches any letter of the alphabet. |
| [^ ] | An excluded character set. This is the opposite of []. If any of the characters inside the brackets exist, the regular expression match fails. You can specify a range of characters by using a hyphen. For example, [^a-zA-Z] ensures that none of the letters in the alphabet are present. |
| ( ) | A group expression. This groups an expression into an item that you can apply special characters to. For example, "a*(ba)+" matches "ba" "aba" or "ababa" but does not match "abbba" or "abaa" |
Examples
| Expression | Meaning |
|---|---|
| [a-zA-Z]+ | The text contains only letters of the alphabet. |
| ^\* | The text begins with an asterisk. |
| (abc|def)$ | The end of the text is either "abc" or "def". |
| Ha..y | The text begins with "Ha" followed by any two characters followed by a "y". |
| Help.* | The text is "Help" followed by any number of other characters. |
See Also