Inserts a new instance of a family into the document, using a location, type/symbol, the host element and a reference direction. 
   Namespace:   Autodesk.Revit.Creation  
  Assembly:   RevitAPI  (in RevitAPI.dll) Version: 16.0.0.0 (16.0.0.0) 
Syntax
| C# | 
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| Visual Basic | 
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| Visual C++ | 
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Parameters
- location
 -  Type:  Autodesk.Revit.DB XYZ  
The physical location where the instance is to be placed. 
- symbol
 -  Type:  Autodesk.Revit.DB FamilySymbol  
A FamilySymbol object that represents the type of the instance that is to be inserted. 
- referenceDirection
 -  Type:  Autodesk.Revit.DB XYZ  
A vector that dictates the direction of certain family instances. 
- host
 -  Type:  Autodesk.Revit.DB Element  
A host object into which the instance will be embedded 
- structuralType
 -  Type:  Autodesk.Revit.DB.Structure StructuralType  
If structural then specify the type of the component. 
Return Value
If creation was successful then an instance to the new object is returned, otherwise a null reference ( Nothing in Visual Basic) .Remarks
 This method allows you to create FamilyInstance objects that require both a location and direction. If the instance fails to be created an exception may be thrown. 
 The type/symbol that is used must be loaded into the document before this method is called. Families and their symbols can be loaded using the Document.LoadFamily or Document.LoadFamilySymbol methods.
Some Families, such as Beams, have more than one endpoint and are inserted in the same manner as single point instances. Once inserted these linear family instances can have their endpoints changed by using the instance's Element.Location property.
Note: if the created family instance includes nested instances, the API framework will automatically regenerate the document during this method call.
Examples
// Get a floor to place the beds
 FilteredElementCollector collector = new FilteredElementCollector(document);
 Floor floor = collector.OfClass(typeof(Floor)).FirstElement() as Floor;
 if (floor != null)
 {
     // Find a Bed-Box family
     Family family = null;
     FilteredElementCollector famCollector = new FilteredElementCollector(document);
     famCollector.OfClass(typeof(Family));
     ICollection<Element> collection = famCollector.ToElements();
     foreach (Element element in collection)
     {
         if (element.Name.CompareTo("Bed-Box") == 0)
         {
             family = element as Family;
             break;
         }
     }
     if (family != null)
     {
         // Enumerate the beds in the Bed-Box family
         FilteredElementCollector fsCollector = new FilteredElementCollector(document);
         ICollection<Element> fsCollection = fsCollector.WherePasses(new FamilySymbolFilter(family.Id)).ToElements();
         IEnumerator<Element> symbolItor = fsCollection.GetEnumerator();
         int x = 0, y = 0;
         int i = 0;
         while (symbolItor.MoveNext())
         {
             FamilySymbol symbol = symbolItor.Current as FamilySymbol;
             XYZ location = new XYZ(x, y, 0);
             XYZ direction = new XYZ();
             switch (i % 3)
             {
                 case 0:
                     direction = new XYZ(1, 1, 0);
                     break;
                 case 1:
                     direction = new XYZ(0, 1, 1);
                     break;
                 case 2:
                     direction = new XYZ(1, 0, 1);
                     break;
             }
             FamilyInstance instance = document.Create.NewFamilyInstance(location, symbol, direction, floor, StructuralType.NonStructural);
             x += 10;
             i++;
         }
     }
 } ' Get a floor to place the beds
Dim collector As New FilteredElementCollector(document)
Dim floor As Floor = TryCast(collector.OfClass(GetType(Floor)).FirstElement(), Floor)
If floor IsNot Nothing Then
    ' Find a Bed-Box family
    Dim family As Family = Nothing
    Dim famCollector As New FilteredElementCollector(document)
    famCollector.OfClass(GetType(Family))
    Dim collection As ICollection(Of Element) = famCollector.ToElements()
    For Each element As Element In collection
        If element.Name.CompareTo("Bed-Box") = 0 Then
            family = TryCast(element, Family)
            Exit For
        End If
    Next
    If family IsNot Nothing Then
        ' Enumerate the beds in the Bed-Box family
        Dim fsCollector As New FilteredElementCollector(document)
        Dim fsCollection As ICollection(Of Element) = fsCollector.WherePasses(New FamilySymbolFilter(family.Id)).ToElements()
        Dim symbolItor As IEnumerator(Of Element) = fsCollection.GetEnumerator()
        Dim x As Integer = 0, y As Integer = 0
        Dim i As Integer = 0
        While symbolItor.MoveNext()
            Dim symbol As FamilySymbol = TryCast(symbolItor.Current, FamilySymbol)
            Dim location As New XYZ(x, y, 0)
            Dim direction As New XYZ()
            Select Case i Mod 3
                Case 0
                    direction = New XYZ(1, 1, 0)
                    Exit Select
                Case 1
                    direction = New XYZ(0, 1, 1)
                    Exit Select
                Case 2
                    direction = New XYZ(1, 0, 1)
                    Exit Select
            End Select
            Dim instance As FamilyInstance = document.Create.NewFamilyInstance(location, symbol, direction, floor, StructuralType.NonStructural)
            x += 10
            i += 1
        End While
    End If
End If Exceptions
| Exception | Condition | 
|---|---|
| Autodesk.Revit.Exceptions ArgumentException | Thrown if The symbol is not active. |