LabelClass

Resumen

Provides access to a layer's label class properties.

Debate

The LabelClass object is used for managing labeling properties such as label expressions or SQL queries that are associated with a layer's individual label classes. The listLabelClasses method on the Layer object will return a list of LabelClass objects.

Not all layers support labeling, so it is useful to test this ahead of time using the supports method on the Layer object. For example:

if lyr.supports("SHOWLABELS"):

If this statement is True, you will be able to modify all label class properties.

Propiedades

Propiedad	Explicación	Tipo de datos
expression (Lectura y escritura)	A layer's individual label class expression using either a VBScript, JScript, or Python parser associated with the label class.	String
name (Lectura y escritura)	A layer's individual label class name.	String
SQLQuery (Lectura y escritura)	A layer's individual label class SQLQuery. This is useful for restricting labels to certain features.	String
visible (Lectura y escritura)	If True, the label class is visible. If False, it is not visible.	Boolean

Muestra de código

LabelClass example 1

The following script will print the label class properties for only those layers that have labels turned on and supports the showLabels property.

import arcpy
aprx = arcpy.mp.ArcGISProject(r"C:\Projects\YosemiteNP\Yosemite.aprx")
m = aprx.listMaps("Yosemite National Park")[0]

for lyr in m.listLayers():
    if lyr.supports("SHOWLABELS"):
        if lyr.showLabels:
            print("Layer name: " + lyr.name)
            for lblClass in lyr.listLabelClasses():
                print("\t Class Name: \t" + lblClass.name)
                print("\t Expression: \t" + lblClass.expression)
                print("\t SQL Query:  \t" + lblClass.SQLQuery)
del aprx

LabelClass example 2

The following script finds a layer named Points of Interest and changes the label class properties for a particular label class named Summit so that not all of the summits are labeled. Only those over 2,000 meters in elevation are labeled.

import arcpy
aprx = arcpy.mp.ArcGISProject(r"C:\Projects\YosemiteNP\Yosemite.aprx")
m = aprx.listMaps("Yosemite National Park")[0]

lyr = m.listLayers("Points of Interest")[0]

if lyr.supports("SHOWLABELS"):
  lblClass = lyr.listLabelClasses("Summit")[0]
  lblClass.expression = "Name"
  lblClass.SQLQuery = "Type_ = 'summit' And Elevation > 2000"
  lblClass.visible = True

aprx.save()
del aprx