Only run tool if features are selected

Discussion created by mbalwanz on Jul 25, 2011
Latest reply on Jul 26, 2011 by christophfricke
I have created a tool to merge multiple line segments into one and update the attributes.  The tool then deletes the selected features and copies the new combine segment into the original dataset.  The problem I have is that if the tool runs when no features are selected it will merge the entire dataset based on the streetname.

How can I make it so the tool will not run unless features are selected?  It would be nice to have an error message pop up to let the user know they need to select some features.

Any help would be greattly appreciated.