Managing Model States Edit Scope in Autodesk Inventor 2026 API

by Chandra shekar Gopal,

When working with Model States in Autodesk Inventor, controlling which states are actively being edited becomes crucial—especially when automating complex design workflows. The Inventor API provides powerful control through two key properties:

• MemberEditScope
• ModelStatesInEdit

This article explains how to use these features to manage model states programmatically in Autodesk Inventor 2026.

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Understanding MemberEditScope

The MemberEditScope property determines which model states are affected during an edit operation. It can be one of the following:

Constant	Description
kEditActiveMember	Only the currently active model state is edited.
kEditAllMembers	All model states are edited.
kEditMultipleMembers	Multiple (but not all) model states are in edit mode.

Note: If MemberEditScope returns kEditMultipleMembers, you must use ModelStatesInEdit to identify the specific model states being edited.

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Understanding ModelStatesInEdit

The ModelStatesInEdit property is a read/write collection that explicitly lists which model states are in edit mode.

Behavior Rules:

• If it contains only the active model state, MemberEditScope becomes kEditActiveMember.
• If it contains all model states, MemberEditScope becomes kEditAllMembers.
• If it includes the active model state plus some others, MemberEditScope becomes kEditMultipleMembers.

Best Practice: Always include the active model state when assigning ModelStatesInEdit.

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Example 1: Print the Current MemberEditScope

This VBA macro prints the current edit scope in the Immediate Window:

Sub PrintEditScope()
    Dim modelStates As ModelStates
    Set modelStates = ThisApplication.ActiveDocument.ComponentDefinition.modelStates

    Select Case modelStates.MemberEditScope
        Case kEditActiveMember
            Debug.Print "kEditActiveMember"
        Case kEditAllMembers
            Debug.Print "kEditAllMembers"
        Case kEditMultipleMembers
            Debug.Print "kEditMultipleMembers"
    End Select
End Sub

Output Illustration – Example 1

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Example 2: List Model States in Edit Mode

This macro prints the names of model states currently in edit mode:

Sub PrintModelStatesInEdit()
    Dim modelStates As ModelStates
    Set modelStates = ThisApplication.ActiveDocument.ComponentDefinition.modelStates

    Dim inEdit As ObjectCollection
    Set inEdit = modelStates.ModelStatesInEdit

    Dim ms As ModelState
    For Each ms In inEdit
        Debug.Print ms.Name
    Next
End Sub

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Example 3: Modify the Model States in Edit Mode

This macro dynamically updates which model states are in edit mode without using the Inventor UI:

Sub ModifyMultipleModelStatesSample()
    Dim oModelStates As ModelStates
    Set oModelStates = ThisApplication.ActiveDocument.ComponentDefinition.modelStates

    Dim oCol As ObjectCollection
    Set oCol = ThisApplication.TransientObjects.CreateObjectCollection

    ' Activate Model State 2
    Dim oMS As ModelState
    Set oMS = oModelStates.Item(2)
    oMS.Activate

    ' Include ModelState2 to ModelState4 in edit mode
    Dim i As Integer
    For i = 2 To 4
        oCol.Add oModelStates.Item(i)
    Next i

    oModelStates.ModelStatesInEdit = oCol
End Sub

Output Illustration – Example 3

🔄 Before and After:

• Before running: Only Model State 1 is in edit mode.
• After running:
  • Model State 2 becomes active.
  • Model States 2, 3, and 4 are now in edit mode.

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🔑 Key Takeaways

• MemberEditScope defines how many model states are being edited.
• ModelStatesInEdit gives precise control over which model states are in edit mode.
• Always include the active model state when using ModelStatesInEdit.
• Use these properties to automate complex modeling scenarios across design variants.

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Why This Matters

Model States are essential for representing different design variants or manufacturing stages within a single Inventor file.

Controlling how and which states are edited programmatically is vital for:

• Efficient model management
• Automating large assemblies
• Dynamically generating manufacturing configurations

By leveraging MemberEditScope and ModelStatesInEdit, you gain full control over your Inventor automation workflows!