Résumé
The EsriTimeDelta class represents a duration, the difference between two dates or times.
Discussion
The EsriTimeDelta class is an alternative to the core Python datetime.timedelta and uses internal Esri time units for intervals that can't be handled by the core Python timedelta object (such as months, weeks, and so on).
The timeStepInterval property from the LayerTime and DataFrameTime classes return EsriTimeDelta objects.
Syntaxe
EsriTimeDelta (interval, units)
Paramètre | Explication | Type de données |
interval | The interval of the EsriTimeDelta. | Double |
units | The units of the EsriTimeDelta. Valid units are milliseconds, seconds, minutes, hours, days, weeks, months, years, decades, and centuries. | String |
Propriétés
Propriété | Explication | Type de données |
interval (Lecture seule) | The interval of the EsriTimeDelta. | Double |
units (Lecture seule) | The units of the EsriTimeDelta. | String |
Exemple de code
EsriTimeDelta example 1
The following script accesses the time-step interval property of a time-enabled layer in a map document. The time-step interval is an EsriTimeDelta object. The script then prints EsriTimeDelta properties.
import arcpy
mxd = arcpy.mapping.MapDocument('C:/Project/Temperature.mxd')
df = arcpy.mapping.ListDataFrames(mxd, 'USA')[0]
lyr = arcpy.mapping.ListLayers(mxd,'temperature', df)[0]
tsi = lyr.time.timeStepInterval
print "Time Step Interval:", tsi
print "EsriTimeDelta interval:", tsi.interval
print "EsriTimeDelta units:", tsi.units
EsriTimeDelta example 2
The following script uses the EsriTimeDelta object to iterate through twelve months starting from the current date.
import arcpy, datetime
time = datetime.datetime.now()
for delta in range(1, 13):
next_date = time + arcpy.time.EsriTimeDelta(1 * delta, "months")
print next_date
EsriTimeDelta example 3
The following script shows how the EsriTimeDelta handles leap years. The script adds a month to January 31, 2008 and returns February 29, 2008.
import arcpy, datetime
time = datetime.datetime(2008, 1, 31)
for delta in range(0, 12):
next_date = time + arcpy.time.EsriTimeDelta(delta, "months")
print next_date
delta = delta + 1