Network Source Directions Field Mapping

描述

网络源方向字段映射对象提供了与数据中的字段相关的信息，这些字段将映射到网络数据集方向配置中的特定属性。

属性

属性	说明	数据类型
againstField （只读）	数据中映射至 key 属性中的指定属性的字段名称，映射目的在于在“至-自”方向（与数字化方向相反）上对线要素进行过渡。	String
alongField （只读）	数据中映射至 key 属性中的指定属性的字段名称，映射目的在于在“自-至”方向（与数字化方向相同）上对线要素进行过渡。	String
key （只读）	数据字段所映射到的网络数据集方向属性的名称。	String
undirectedField （只读）	数据中映射至 key 属性中的指定属性的字段名称，映射目的在于在所有行驶方向上进行过渡。	String

代码示例

网络源方向字段映射示例

# Name: NDSSourceDirectionsFieldMapping_ex01.py
# Description: Print information about the directions field mappings associated
#              with edge sources in the network dataset.

import arcpy
import sys

network = r"C:/Data/NetworkDatasetWithLandmarks.gdb/Transportation/Streets_ND"

# Create Describe object for the network dataset
desc = arcpy.Describe(network)

#If the directions are not set for the network dataset, exit
if not desc.supportsDirections:
    print("No direction information")
    sys.exit()

# Get all the edge sources
sources = desc.edgeSources

#If there are no edge sources in the network dataset, quit.
if not sources:
    print("No edge sources")
    sys.exit()

#Loop through all the edge sources
for source in sources:
    print("\n--------------------")
    print("Edge source name: " , source.name)
    # Get the directions information specific to this edge source
    sDir = source.sourceDirections
    # Check if the edge source has turn and confirmation landmarks associated with it.
    # If so, print some information about the landmarks.
    if hasattr(sDir, "fieldMappings"):
        fieldMappings = sDir.fieldMappings
        print("\n--Field mapping information--")
        for fm in fieldMappings:
            print("\nProperty key:", fm.key)
            print("Along field name:", fm.alongField)
            print("Against field name:", fm.againstField)
            print("Undirected field name:", fm.undirectedField)
    else:
        print("Source does not directions field mappings.")