How to copy some fields from one feature class to an existing fc

Question

I need to copy some fields from one shapefile to another existing one, preferably using Arcpy. Below is my code that checks for common fields between two shapefiles. Can I use this and add code to copy the fields that are not already in the destination shapefile from the original? What function will do that for me? I do not want data to transfer over--just the fields. Thank you!

* >>>#FIELDS is the list of fields from the shapefile to copy from
* #FIELDS2 is the list of fields already in the shapefile to copy to
* fields = arcpy.ListFields("G:/Working Folder/Backup.gdb/PubData_RoadCenterlines")
* ... fields2 = arcpy.ListFields(r"G:\Data\External\Fairfield_County\Dupage_Centerlines_Web_Mercator_1984.shp")
* ... namelist = []
* ... namelist2 = []
* ... x = 0
* ... y = 0
* ... for field in fields:
* ...    #populate NAMELIST[] with FIELDS * namelist.append(field.name)

* ...   #check the to shapefile for fields it already has and are common with the from shapefile* for field2 in fields2:

* ...         namelist2.append(field2.name)
* ...         if namelist2 == namelist:
* ...             print namelist + "is common between the two shapefiles"
* ...        x+=1
* ...     y+=1

MicahBabinski · Answer

Glad to hear it! Since sometimes OID fields have a name besides OBJECTID, an even more robust approach would be: if (field01.type != 'OID'):‍ Happy scripting, Doug.

DougWolfinger2 · Answer

I finally got a chance to get back into this and got it working. I moved the last print statement above the add field call : ... print("The {0} field with a type of {1} and a length of {2} was added to shp 02" ... .format(field[0], field[1], field[2])) ... arcpy.AddField_management(shp02, field[0], field[1], "", "", field[2], "", "NON_NULLABLE","NON_REQUIRED","") ... ..... and got this error message: ... for field in newFields: The OBJECTID field with a type of OID and a length of 4 was added to shp 02 Runtime error Traceback (most recent call last): File "", line 24, in File "j:\apps\arcgis\desktop10.4\arcpy\arcpy\management.py", line 3149, in AddField raise e ExecuteError: ERROR 000800: The value is not a member of TEXT | FLOAT | DOUBLE | SHORT | LONG | DATE | BLOB | RASTER | GUID. So I added a nested IF to bypass the adding of OBJECTID because it looked like it balked at adding it. I suppose this is because every shp has a field like that by default. if (exists == False): ... if (field01.name != 'OBJECTID'): newFields.append([field01.name, field01.type, field01.length]) Thanks again for the assistance!

LeoMontero · Answer

Hi Doug

Please try Micah's suggestion (place print statement before arcpy.AddField_management) to see the properties (name, type, length) of the field you're trying to add.

Regards,

Leo