How to read a String with value "now.tostring" and receive the date in a text box?

I want to know if there is a way to save methods into an Json like text to be read later into uipath.

Normally when we try to show the date we put a “Message Box” activity and we write: now.ToString. And then we have our date.
I want to write “now.ToString” into a .txt file to be read by my robot and when the robot put this String on the “Message Box” activity should be showing the date. But rigth now obviously is showing literaly “now.ToString” and i dont know how to make de robot read this like a c# sentence.

This is the example:

It doesn’t work in that way.
You cannot convert the string variables into code.