# GetMatchRegEx (StartAt)

| **Name**    | ***GetMatchRegEx***                                                                                                                                                                                                 |
| ----------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Syntax      | GetMatchRegEx (String pattern, String str, Integer startAt)                                                                                                                                                         |
| Purpose     | To return a result if a match was found. Otherwise, returns an empty string.                                                                                                                                        |
| Description | Scans the string, starting at the specified (interger) position, for an occurrence of text matching the specified regular expression.                                                                               |
| Return Type | String                                                                                                                                                                                                              |
| Parameters  | <p>pattern \[System.String] – Regular expression pattern to match</p><p>str \[System.String] – String to search for a match</p><p>startAt \[System.Int64] – The character position at which to start the search</p> |

![](/files/Ahi9rDrd6mLEwDlvcfWS)

**Example**

In this example, we will pass the required parameters to the function transformation object using a *Variables* object.

Where,

*Regular Expression (Pattern)* = ^H\[\S]{0,4}|$

*String* = 1234HelloWorld!

*startAt* = 4

{% hint style="info" %}
**Note:** The specified regular expression will look for and match a string which begins with “H” (case sensitive). Next, it will match any character that is not a whitespace character in the next 0 to 4 characters. Finally, the “$” is used to end the string. Therefore, the returned output should be “Hello”, as the *startAt* position is “4”.
{% endhint %}

![](/files/RRgHQ7GcTdRRl6jGxV6q)

In the output window, you can see that Astera has returned a string value, as the regular expression pattern has been matched in accordance with the defined starting position.

![](/files/KmSnAu82v5Tjo15NAoQF)


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