nav[aria-label="Primary Navigation"] { padding: 0; & ul { list-style: none; width: 100%; display: flex; flex-direction: row; justify-content: start; align-items: start; gap: 30px; padding: 0; & li { margin: 0; } & ul li { list-style: none; } } }

Definition query multiple values

AmyKlug

Hi. I want to create a script tool that let's the user select one or more Line ID and set a definition query and I want to choose from a list based on the Line ID field in the feature class (SetParameter?). How can I do that? Not sure if I need to append to a list and if an expression can grow or shrink depending on how many values are selected.

e.g. LineID = '0001' OR LineID = '0002'..................................

Here is the simple (single value) version:

import arcpy
Line_ID = arcpy.GetParameterAsText(0)
mxd = arcpy.mapping.MapDocument("Current")
df = arcpy.mapping.ListDataFrames(mxd, "*")[0]
layer = arcpy.mapping.ListLayers(mxd, "Lines")[0]
sc = set(r[0] for r in arcpy.da.SearchCursor(layer, "LID"))
for s in sc:
    where_clause = "LID = '"+Line_ID+"'"
    layer.definitionQuery = where_clause
    ext = layer.getExtent()
    df.extent = ext
del mxd, df, layer, sc, s

Find more posts tagged with

Accepted answers

XanderBakker

If you want to have the values in the dialog of the tool then this needs to be scripted in the tool validation. For example if you have a tool like this:

and the result is to print a where clause of the values like this:

... the code in the script would be:

import arcpy
fc = arcpy.GetParameterAsText(0)
fld = arcpy.GetParameterAsText(1)
selvals = arcpy.GetParameterAsText(2)

lst_vals = selvals.split(';')
where = "{0} in ('{1}')".format(arcpy.AddFieldDelimiters(fc, fld), "','".join(lst_vals))

arcpy.AddMessage(where)

the validation code for the "updateParameters" function would be:

  def updateParameters(self):
    """Modify the values and properties of parameters before internal
    validation is performed.  This method is called whenever a parameter
    has been changed."""
    if self.params[1].altered:
        if self.params[1]:
            fc = str(self.params[0].value)
            fld = str(self.params[1].value)
            lst_vals = list(set(r[0] for r in arcpy.da.SearchCursor(fc, (fld))))
            self.params[2].filter.list = lst_vals
    return

In the validation, when the selected field is changed and has a value, the fc name and the fld name are read and used for the search cursor to create the list of unique values. This list is assigned to the filter.list of the 3rd parameter.

The parameters are defined as follows:

For the field you can filter the type of fields (optionally), but you will have to define "Obtained from" and select the feature layer.

The list of values is a Multivalue (Yes) and the filter is an empty value list.

All comments

AmyKlug

I can't seem to get the list values to appear after selecting a field (which are numbers stored as text). It tells me I have illegal list values.

Also the only way I can get a field list to appear in the UI is to use a feature class data type (feature layer = nothing). I would like to use feature layer so only layers in the data frame can be used.

Have not started on the definition query part yet.

import arcpy
fc = arcpy.GetParameterAsText(0)    
fld = arcpy.GetParameterAsText(1)
selvals = arcpy.GetParameterAsText(2)

lst_vals = selvals.split(';')  
where = "{0} in ('{1}')".format(arcpy.AddFieldDelimiters(fc, fld), "','".join(lst_vals)) 

arcpy.AddMessage(where)

import arcpy
class ToolValidator(object):
  """Class for validating a tool's parameter values and controlling
  the behavior of the tool's dialog."""
  def __init__(self):
    """Setup arcpy and the list of tool parameters."""
    self.params = arcpy.GetParameterInfo()
  def initializeParameters(self):
    """Refine the properties of a tool's parameters.  This method is
    called when the tool is opened."""
    return
  def updateParameters(self):
    """Modify the values and properties of parameters before internal
    validation is performed.  This method is called whenever a parameter
    has been changed."""
    if self.params[1].altered:  
        if self.params[1].value:  
            fc = str(self.params[0].value)
            fld = str(self.params[1].value) 
            lst_vals = list(set(r[0] for r in arcpy.da.SearchCursor(fc, (fld))))
            #self.params[1].filter.list = [str(field.name) for field in arcpy.Describe(fc).fields]
            self.params[2].filter.list = lst_vals
    return
  def updateMessages(self):
    """Modify the messages created by internal validation for each tool
    parameter.  This method is called after internal validation."""
    return

XanderBakker

Combing your code with my example would yield something like:

import arcpy
fc = arcpy.GetParameterAsText(0)
fld = arcpy.GetParameterAsText(1)
lst_vals = arcpy.GetParameter(2)

where = "{0} in ('{1}')".format(arcpy.AddFieldDelimiters(fc, fld), "','".join(lst_vals))
arcpy.AddMessage(where)

mxd = arcpy.mapping.MapDocument("Current")
df = arcpy.mapping.ListDataFrames(mxd, "*")[0]
layer = arcpy.mapping.ListLayers(mxd, fc)[0] # assuming that the layer is selected from the TOC

layer.definitionQuery = where
ext = layer.getExtent()
df.extent = ext
del mxd, df, layer

If the idea is to zoom in to the selected items...

AmyKlug

How do you set up the expression for the definition query?

XanderBakker

If you want to have the values in the dialog of the tool then this needs to be scripted in the tool validation. For example if you have a tool like this:

and the result is to print a where clause of the values like this:

... the code in the script would be:

import arcpy
fc = arcpy.GetParameterAsText(0)
fld = arcpy.GetParameterAsText(1)
selvals = arcpy.GetParameterAsText(2)

lst_vals = selvals.split(';')
where = "{0} in ('{1}')".format(arcpy.AddFieldDelimiters(fc, fld), "','".join(lst_vals))

arcpy.AddMessage(where)

the validation code for the "updateParameters" function would be:

  def updateParameters(self):
    """Modify the values and properties of parameters before internal
    validation is performed.  This method is called whenever a parameter
    has been changed."""
    if self.params[1].altered:
        if self.params[1]:
            fc = str(self.params[0].value)
            fld = str(self.params[1].value)
            lst_vals = list(set(r[0] for r in arcpy.da.SearchCursor(fc, (fld))))
            self.params[2].filter.list = lst_vals
    return

The parameters are defined as follows:

For the field you can filter the type of fields (optionally), but you will have to define "Obtained from" and select the feature layer.

The list of values is a Multivalue (Yes) and the filter is an empty value list.

Join the Conversation

Signed in members can post, follow updates, and more. New here? Register a free account.

Quick Links

Community Help
Find useful guides, FAQs, and documents to help you navigate and make the most of Esri Community.