You have a string value of a CSV file and you are looking to send it as an attachment using the Send Mail As Impersonated User action via the Microsoft Graph integration which requires the CSV string to be base64 encoded.
Overview
Encode a string in base64.
Parameters
Parameter
Description
Required
String
String to encode
URL Safe
Whether to return a URL-safe base64 format. '-' is used instead of '+', and '_' instead of '/'.
Usage
Example 1: Encoding a String
Inputs:
**String**: This @is my test string-yeeeehaw
**URL Safe**: false