No grid rows selected: On a screen with a grid control I have added a pushbutton that invokes an InputScript. Is there a way to stop processing the InputScript associated with the pushbutton if no grid control rows have been selected?

The best way to stop further processing is a "Return" statement, provided you have not yet processed a "Screen" command in the InputScript.

In the case that you describe you need to process a VBScript before knowing that no grid rows have been selected. You need to write a temporary file in the VBScript that you read in the InputScript. For details please see example 9 in