Model Builder Delete Feature Class problem

Question

How do I add the Delete tool to my Model if the feature class doesn't exist?  It will be unknown at runtime whether the feature class will exist and I want it to delete the feature class if it does exist.  However it seems that I can only add the Delete tool if the feature class exists.  How do you experts get around this "bug/feature"?

Thanks

gpnobbir · Answer

One way to get it done is to make the input parameter of the script tool optional and make the output parameter derived.

BrentHoskisson · Answer

Create a dummy feature class in the place where your feature class could exists or not (location) such the your feature class exists. Run the model once based on this blog
If you are stuck at "if" �?? Part 1. This blog has an example for your case.

Off topic.  Have you tested your "If Feature Class Exists" on this blog with SDE layers?  I get false even if the feature class does exist (my other similar scripts return true with the same info).

BrentHoskisson · Answer

I attached the simplest model that breaks.  Here is the code inside "Conditional Delete".  It will not even start if the feature class doesn't exist, but the whole point of the script is to see if the feature class exists first.

import sys, os, arcpy

# Get the input from the model
InputFC = arcpy.GetParameterAsText(0)

# Statement to check the existence of the feature class
if arcpy.Exists(InputFC):
    arcpy.AddMessage("Feature Class Exists and will be deleted!")
    arcpy.Delete_management(InputFC, "FeatureClass")
arcpy.SetParameterAsText(1,"True")

Model.png