删除字段 (数据管理)

摘要

可从表、要素类、要素图层或栅格数据集中删除一个或多个字段。

使用情况

• 不能从 ArcGIS 的非本地只读数据格式中删除字段，例如：VPF 和 CAD 数据集。

参数

对话框

标注	说明	数据类型
输入表	包含要删除字段的表。将修改现有输入表。	Mosaic Layer; Raster Layer; Table View
删除字段	要从输入表中删除的字段。必填字段不能删除。	Field

派生输出

标注	说明	数据类型
更新输入表	已更新的数据集。	表视图；栅格图层；镶嵌图层

Python

arcpy.management.DeleteField(in_table, drop_field)

名称	说明	数据类型
in_table	包含要删除字段的表。将修改现有输入表。	Mosaic Layer; Raster Layer; Table View
drop_field [drop_field,...]	要从输入表中删除的字段。必填字段不能删除。	Field

派生输出

名称	说明	数据类型
out_table	已更新的数据集。	表视图；栅格图层；镶嵌图层

代码示例

DeleteField 示例（Python 窗口）

以下 Python 窗口脚本演示了如何在即时模式下使用 DeleteField 函数。

import arcpy
arcpy.env.workspace = "C:/data"
arcpy.CopyFeatures_management("majorrds.shp", "C:/output/majorrds_copy.shp")
arcpy.DeleteField_management("C:/output/majorrds_copy.shp", 
                             ["STREET_NAM", "LABEL", "CLASS"])

DeleteField 示例 2（独立脚本）

以下独立脚本演示了如何使用 DeleteField 函数。

# Name: DeleteField_Example2.py
# Description: Delete several fields from a feature class
  
# Import system modules
import arcpy
 
# Set environment settings
arcpy.env.workspace = "C:/data"
 
# Set local variables
inFeatures = "accident.dbf"
outFeatureClass = "C:/output/new_accident.dbf"
dropFields = ["STREET_NAM", "LABEL", "CLASS"]
 
# Execute CopyFeatures to make a new copy of the feature class
#  Use CopyRows if you have a table
arcpy.CopyFeatures_management(inFeatures, outFeatureClass)
 
# Execute DeleteField
arcpy.DeleteField_management(outFeatureClass, dropFields)

DeleteField 示例 3（独立脚本）

可以使用 DeleteField 函数从要素类或表中删除所有不需要的字段。

# Description: Delete unnecessary fields from a feature class or table.
 
# Import system modules
import arcpy
 
# Get user-supplied input and output arguments
inTable = arcpy.GetParameterAsText(0)
updatedTable = arcpy.GetParameterAsText(1)
# Describe the input (need to test the dataset and data types)
desc = arcpy.Describe(inTable)
# Make a copy of the input (so we can mantain the original as is)
if desc.datasetType == "FeatureClass":
    arcpy.CopyFeatures_management(inTable, updatedTable)
else:
    arcpy.CopyRows_management(inTable, updatedTable)
# Use ListFields to get a list of field objects
fieldObjList = arcpy.ListFields(updatedTable)
# Create an empty list that will be populated with field names        
fieldNameList = []
# For each field in the object list, add the field name to the
#  name list.  If the field is required, exclude it, to prevent errors
for field in fieldObjList:
    if not field.required:
        fieldNameList.append(field.name)
# dBASE tables require a field other than an OID and Shape.  If this is
#  the case, retain an extra field (the first one in the original list)
if desc.dataType in ["ShapeFile", "DbaseTable"]:
    fieldNameList = fieldNameList[1:]
# Execute DeleteField to delete all fields in the field list. 
arcpy.DeleteField_management(updatedTable, fieldNameList)

环境

当前工作空间

特殊情况

许可信息

• Basic: 是
• Standard: 是
• Advanced: 是