ElementParameterFilter Class

A filter used to match elements by one or more parameter filter rules.

Inheritance Hierarchy

System.Object
  Autodesk.Revit.DB.ElementFilter
    Autodesk.Revit.DB.ElementSlowFilter
      Autodesk.Revit.DB.ElementParameterFilter

Namespace: Autodesk.Revit.DB
Assembly: RevitAPI (in RevitAPI.dll) Version: 25.3.0.0 (25.3.0.0)

Syntax

C#

public class ElementParameterFilter : ElementSlowFilter

The ElementParameterFilter type exposes the following members.

Constructors

	Name	Description
	ElementParameterFilter(FilterRule)	Constructs a new instance of an ElementParameterFilter from a single rule.
	ElementParameterFilter(IList<FilterRule>)	Constructs a new instance of an ElementParameterFilter from a set of rules.
	ElementParameterFilter(FilterRule, Boolean)	Constructs a new instance of an ElementParameterFilter, with the option to match all elements not passing a given filter rule.
	ElementParameterFilter(IList<FilterRule>, Boolean)	Constructs a new instance of an ElementParameterFilter, with the option to match all elements not passing the given filter rules.

Properties

	Name	Description
	Inverted	True if the results of the filter are inverted; elements that would normally be accepted by this filter will be rejected, and elements that would normally be rejected will be accepted. (Inherited from ElementFilter)
	IsValidObject	Specifies whether the .NET object represents a valid Revit entity. (Inherited from ElementFilter)

Methods

	Name	Description
	Dispose	(Inherited from ElementFilter)
	Equals	Determines whether the specified object is equal to the current object. (Inherited from Object)
	GetHashCode	Serves as the default hash function. (Inherited from Object)
	GetRules	Returns the set of rules contained in this filter.
	GetType	Gets the Type of the current instance. (Inherited from Object)
	PassesFilter(Element)	Applies the filter to a given element. (Inherited from ElementFilter)
	PassesFilter(Document, ElementId)	Applies the filter to a given element. (Inherited from ElementFilter)
	ToString	Returns a string that represents the current object. (Inherited from Object)

Remarks

This filter is a slow filter. Slow filters require that the Element be obtained and expanded in memory first. Thus it is preferable to couple this filter with at least one ElementQuickFilter, which should minimize the number of Elements that are expanded.

Example

C#

// Creates an ElementParameter filter to find rooms whose area is 
// greater than specified value
// Create filter by provider and evaluator 
// provider
ParameterValueProvider pvp = new ParameterValueProvider(new ElementId(BuiltInParameter.ROOM_AREA));
// evaluator
FilterNumericRuleEvaluator fnrv = new FilterNumericGreater();
// rule value    
double ruleValue = 100.0f; // filter room whose area is greater than 100 SF
// rule
FilterRule fRule = new FilterDoubleRule(pvp, fnrv, ruleValue, 1E-6);

// Create an ElementParameter filter
ElementParameterFilter filter = new ElementParameterFilter(fRule);

// Apply the filter to the elements in the active document
FilteredElementCollector collector = new FilteredElementCollector(document);
IList<Element> rooms = collector.WherePasses(filter).ToElements();


// Find rooms whose area is less than or equal to 100: 
// Use inverted filter to match elements
ElementParameterFilter lessOrEqualFilter = new ElementParameterFilter(fRule, true); 
collector = new FilteredElementCollector(document);
IList<Element> lessOrEqualFounds = collector.WherePasses(lessOrEqualFilter).ToElements();

VB

' Creates an ElementParameter filter to find rooms whose area is 
' greater than specified value
' Create filter by provider and evaluator 
' provider
Dim pvp As New ParameterValueProvider(New ElementId(BuiltInParameter.ROOM_AREA))
' evaluator
Dim fnrv As FilterNumericRuleEvaluator = New FilterNumericGreater()
' rule value    
Dim ruleValue As Double = 100.0F
' filter room whose area is greater than 100 SF
' rule
Dim fRule As FilterRule = New FilterDoubleRule(pvp, fnrv, ruleValue, 0.000001)

' Create an ElementParameter filter
Dim filter As New ElementParameterFilter(fRule)

' Apply the filter to the elements in the active document
Dim collector As New FilteredElementCollector(document)
Dim rooms As IList(Of Element) = collector.WherePasses(filter).ToElements()


' Find rooms whose area is less than or equal to 100: 
' Use inverted filter to match elements
Dim lessOrEqualFilter As New ElementParameterFilter(fRule, True)
collector = New FilteredElementCollector(document)
Dim lessOrEqualFounds As IList(Of Element) = collector.WherePasses(lessOrEqualFilter).ToElements()