ArcPy Script: Field Mappings Parameter and Object in Python Toolbox help

BrianLai1 — Mon, 28 Jul 2014 15:20:42 GMT

So I'm trying to create a Field Mappings input parameter for the ArcPy Spatial Join Analysis tool, but it spits up an error. When I try to create a Field Mapping object in the execute portion of my test script, I can successfully add Field Maps objects to the Field Mappings object. Below is an example of the error I get when trying to update the fields in updateParameters():

ValueError: FieldMappings:

AddFieldMap input not field map object

###################################################

This is the code:

def getParameterInfo(self):

targetfeatures= arcpy.Parameter(

displayName = "",

name = "",

datatype = "Feature Class",

parameterType = "Required",

direction = "Input")

fieldmapping= arcpy.Parameter(

displayName = "",

name = "",

datatype = "Field Mappings",

parameterType = "Required",

direction = "Input")

fieldmapping.value = str('Empty') #If I don't include this line, I get an error: AttributeError: 'NoneType' object has no attribute 'addFieldMap'

parameters = [targetfeatures, fieldmapping]

return parameters

def updateParameters(self, parameters): #optional

joinFeatures = parameters[0].value

joinfieldmap = arcpy.FieldMap()

joinfields = arcpy.ListFields(joinFeatures)

for joinfield in joinfields:

joinfieldname = unicodedata.normalize('NFKD', joinfield.name).encode('ascii','ignore')

try:

joinfieldmap.addInputField(joinFeatures, joinfieldname)

except:

pass

parameters[1].value.addFieldMap(joinfieldmap)

return

Re: ArcPy Script: Field Mappings Parameter and Object in Python Toolbox help

DanPatterson_Retired — Mon, 28 Jul 2014 15:25:19 GMT

is it because you are missing an extra bracket in this line?

fieldmapping.value = str('Empty')

should it be

fieldmapping.value = str('Empty') )

Re: ArcPy Script: Field Mappings Parameter and Object in Python Toolbox help

BrianLai1 — Mon, 28 Jul 2014 16:41:41 GMT

That bit works just fine. My field mappings parameters does have its default value set to 'Empty'. The problem is in updating the parameter once I input a feature class. What I want it to do is pull fields from the feature class and display them in my field mappings parameter. Sorry I should I have mentioned that.

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ArcPy Script: Field Mappings Parameter and Object in Python Toolbox help

Re: ArcPy Script: Field Mappings Parameter and Object in Python Toolbox help

Re: ArcPy Script: Field Mappings Parameter and Object in Python Toolbox help