# IndexOf

| **Name**    | ***IndexOf***                                                                                                                                                          |
| ----------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Syntax      | IndexOf (String lookIn, String lookFor)                                                                                                                                |
| Purpose     | To return the index of a specified lookFor string after searching the lookIn string.                                                                                   |
| Description | Returns an integer representing the starting position of lookFor, in lookIn. If lookFor was not found in lookIn or either lookFor or lookIn is null, -1 is returned.   |
| Return Type | Int64                                                                                                                                                                  |
| Parameters  | <p>lookIn \[System.String] – String to search in</p><p>lookFor \[System.String] – String to search for</p><p>isCaseSensitive \[System.Boolean] – Is Case Sensitive</p> |

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/0%20\(210\).png)

**Example**

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

Where,

*lookIn* = ABCDEFG

*lookFor* = c

*isCaseSensitive* = False

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/1%20\(210\).png)

Right-click on the function transformation object and select *Preview Output.* You can see that Astera Data Stack has returned the integer value, “2”, indicating that the specified *lookFor* string is in the outputted index value position, “2”.

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/2%20\(208\).png)