For custom code the args array is structured as follows:
args[] is contains two objects: The first argument args[0] is the Cell object in its entirety, which contains a variety of cell attribute information including row and col indices, cell type, format, convenience flags, linked report data, etc. The second argument args[1] provides the raw text of the cell as a string.
For .Net Assemblies the method signature is as follows:
string EventHandlerName(SessionInfo sessionInfo, Cell cell, string rawCellText)
The event expects a string or null return value. If null is returned, the event will interpret this as a flag indicating that no custom CSV data is being provided, and to return the report’s CSV output. If a string is returned (including an empty string), the cell will output the string as provided, overriding the report data for that cell.