Execute either a custom node or a CSV Reader

Hello

I have a custom node which has no input port and one output port. Depending on a variable, I want to execute either the custom node or to read data from a CSV file (using CSV Reader for example). If data is read from the CSV file, I do not want to execute the custom node at all.

How can i do this? 

 

Look at the switching nodes

"CASE Switch Model (Start)" node is the solution.