# GetFileExtension (String filePath)

| **Name**    | ***GetFileExtension***                                      |
| ----------- | ----------------------------------------------------------- |
| Syntax      | GetFileExtension (String filePath)                          |
| Purpose     | To return file extension from the specified file path.      |
| Description | Extracts file extension from the given file path.           |
| Return Type | String                                                      |
| Parameter   | filePath \[System.String] – Full path of the file to check. |

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/0%20\(195\).png)

**Example**

In this example, we are passing the required parameter to the function transformation object using a *Variables* object. We will be defining the file path of the file for which we want to extract the extension.

Where,

*filePath* = *C:\Users\Kanwal.Azim\OneDrive - Astera Software\Desktop\Functions Documentation\Files\GetFileExtension\GetFileExtension.docx*

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/1%20\(195\).png)

Right-click on the function transformation object and select *Preview Output.* As you can see, Astera Data Stack has returned the extracted file extension from the specified file path.

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/2%20\(195\).png)


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