Here is a way to check if a Field in a feature class already exists or not. I was looking for an existing ArcGIS Esri function / tool but couldn’t find one so I wrote my own.
def FieldExist(featureclass, fieldname): fieldList = arcpy.ListFields(featureclass, fieldname) fieldCount = len(fieldList) if (fieldCount == 1): return True else: return False
This is a function and it assumes you have already set the workspace environment.
if (not FieldExist(myFeatureClass, "myField")): arcpy.AddError("Field 'myField' does not exist in " + myFeatureClass) sys.exit()
hope this is helpful.