Dynamo Script to retrieve all elements by category and view from Revit.

Dynamo_ElementsByCategoryAndView.py

# To be pasted in a Dynamo Python Script node.
import clr
 
clr.AddReference('RevitAPI')
from Autodesk.Revit.DB import *
 
clr.AddReference("RevitServices")
import RevitServices
from RevitServices.Persistence import DocumentManager

import System

doc = DocumentManager.Instance.CurrentDBDocument
category = UnwrapElement(IN[0])
bic = System.Enum.ToObject(BuiltInCategory, category.Id.IntegerValue)
view = UnwrapElement(IN[1])
 
OUT = FilteredElementCollector(doc, view.Id).OfCategory(bic).ToElements()