As Title .

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Imports System

Imports EnvDTE

Imports System.Diagnostics


Public Module CollapseAll

    Sub CollapseAll()

        ' Get the the Solution Explorer tree

        Dim UIHSolutionExplorer As UIHierarchy

        UIHSolutionExplorer = DTE.Windows.Item(Constants.vsext_wk_SProjectWindow).Object()

        ' Check if there is any open solution

        If (UIHSolutionExplorer.UIHierarchyItems.Count = 0) Then

            ' MsgBox("Nothing to collapse. You must have an open solution.")

            Return

        End If

        ' Get the top node (the name of the solution)

        Dim UIHSolutionRootNode As UIHierarchyItem

        UIHSolutionRootNode = UIHSolutionExplorer.UIHierarchyItems.Item(1)

        UIHSolutionExplorer = Nothing

        UIHSolutionRootNode.DTE.SuppressUI = True

        ' Collapse each project node

        Dim UIHItem As UIHierarchyItem

        For Each UIHItem In UIHSolutionRootNode.UIHierarchyItems

            'UIHItem.UIHierarchyItems.Expanded = False

            If UIHItem.UIHierarchyItems.Expanded Then

                Collapse(UIHItem)

            End If

        Next

        ' Select the solution node, or else when you click

        ' on the solution window

        ' scrollbar, it will synchronize the open document

        ' with the tree and pop

        ' out the corresponding node which is probably not what you want.

        UIHSolutionRootNode.Select(vsUISelectionType.vsUISelectionTypeSelect)

        UIHSolutionRootNode.DTE.SuppressUI = False

        UIHSolutionRootNode = Nothing

    End Sub


    Private Sub Collapse(ByVal item As UIHierarchyItem)

        For Each eitem As UIHierarchyItem In item.UIHierarchyItems

            If eitem.UIHierarchyItems.Expanded AndAlso eitem.UIHierarchyItems.Count > 0 Then

                Collapse(eitem)

            End If

        Next

        item.UIHierarchyItems.Expanded = False

    End Sub

End Module 

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