# Extract (String)

| **Name**    | ***Extract***                                                                                                                                                                                                                                                            |
| ----------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| Syntax      | Extract (String str, String start)                                                                                                                                                                                                                                       |
| Purpose     | To return string enveloped between specified *start* and *end* values within the *str* value.                                                                                                                                                                            |
| Description | Returns a string enveloped between ‘start’ string and ‘end’ string. If ‘end’ is omitted, string starting after ‘start’ is returned. Case sensitivity can be specified by the user, using Boolean values, True or False.                                                  |
| Return Type | String                                                                                                                                                                                                                                                                   |
| Parameters  | <p>str \[System.String] – The string to search in</p><p>start \[System.String] – The beginninh part of the string to search for</p><p>end \[System.String] – The optional ending of the string to search for</p><p>isCaseSensitive \[System.Boolean] – True to match</p> |

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/0%20\(226\).png)

**Example**

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

Where,

*str* = helloABCworld

*start* = o

*end* = W

*isCaseSensitive* = False

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/1%20\(226\).png)

Right-click on the function transformation object and select *Preview Output.* You can see that Astera Data Stack has returned ABC, the value enveloped between the *start* value *“o” and NOT case sensitive end value,* “W”.

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/2%20\(224\).png)


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