Summary
Adds a custom error message (severity of 2) to the messages of a script tool or Python toolbox tool.
When a tool is run, arcpy is fully aware of the application it is called from. One major effect of this is that you can write messages in Python and your messages automatically appear on the tool dialog box, in the history, and the Python window.
Syntax
AddError (message)
| Parameter | Explanation | Data Type |
message | The error message to add. | String |
Code sample
Add a custom geoprocessing error message.
import arcpy
fc = arcpy.GetParameterAsText(0)
# Get the count from GetCount's Result object
feature_count = int(arcpy.GetCount_management(fc).getOutput(0))
if feature_count == 0:
arcpy.AddError("{0} has no features.".format(fc))
else:
arcpy.AddMessage("{0} has {1} features.".format(fc, feature_count))