# LeftOf (String)

| **Name**    | ***LeftOf***                                                                                                                                                      |
| ----------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Syntax      | LeftOf (String str, String lookFor)                                                                                                                               |
| Purpose     | To search str for lookFor and, if found, to return all characters before it.                                                                                      |
| Description | If the string is found, returns all the characters to the left of the specified string. Otherwise, returns an empty string.                                       |
| Return Type | String                                                                                                                                                            |
| Parameters  | <p>str \[System.String] – String that will be searched and whose part will be returned</p><p>lookFor \[System.String]</p><p>isCaseSensitive \[System.Boolean]</p> |

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/0%20\(70\).png)

**Example**

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

Where,

*str* = ABCDEFG

*lookFor* = e

*isCaseSensitive* = False

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/1%20\(71\).png)

Right-click on the function transformation object and select *Preview Output.* You can see that Astera Data Stack has returned all the characters to the left of the specified string value.

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/2%20\(71\).png)


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