“Fulltrim” would be the better solution here, but if you’re wanting to use “Evaluate”, you have to understand that you’re building a string to be evaluated. Thus, “strD” in your current code is considered part of the string that you’re evaluating. Notes doesn’t have a value for that “variable”, so it’s null.
What you’re wanting to do is:
newVal = Evaluate ( {@Trim (} & strD & {)} )
…so that the VALUE of strD gets inserted into the string to evaluate.