ListView.ListViewItemSorter Property


Gets or sets the sorting comparer for the control.

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

Public Property ListViewItemSorter As IComparer

Property Value

Type: System.Collections.IComparer

An IComparer that represents the sorting comparer for the control.

The ListViewItemSorter property allows you to specify the object that performs the sorting of items in a ListView control when the Sort method is called or when items are added to the list. Note that items are not sorted automatically when their label text changes.

The specified object must be an instance of a class that implements the IComparer interface, which has a single method called Comparer.Compare.

You can use this property to provide custom sorting, for example, when a column header is clicked in the details view. To do this, create a class that implements the IComparer interface and provides a constructor that accepts the index of a column to sort by. You can then implement a handler for the ColumnClick event that creates an instance of this class using the index of the clicked column. When you set the ListViewItemSorter property to the new instance, the ListView control is automatically sorted using the specified object. Subsequent calls to the Sort method use the same object.


When you set the value of the ListViewItemSorter property, the Sort method is called automatically.

The following code example creates a form that contains a ListView control that manually sorts items when a column in the ListView control is clicked. The example defines a class called ListViewItemComparer that implements the System.Collections.IComparer interface that performs the ListViewItem comparison. The example creates an instance of ListViewItemComparer and uses it to set the ListViewItemSorter property of the ListView control. The Sort method call in the ColumnClick event handler uses the methods defined in ListViewItemComparer to perform the sort of items, based on the column that is clicked.

Imports System
Imports System.Windows.Forms
Imports System.Drawing
Imports System.Collections

Namespace ListViewSortFormNamespace

    Public Class ListViewSortForm
        Inherits Form

        Private listView1 As ListView

        Public Sub New()
            ' Create ListView items to add to the control.
            Dim listViewItem1 As New ListViewItem(New String() {"Banana", "a", "b", "c"}, -1, Color.Empty, Color.Yellow, Nothing)
            Dim listViewItem2 As New ListViewItem(New String() {"Cherry", "v", "g", "t"}, -1, Color.Empty, Color.Red, New Font("Microsoft Sans Serif", 8.25F, FontStyle.Regular, GraphicsUnit.Point, CType(0, System.Byte)))
            Dim listViewItem3 As New ListViewItem(New String() {"Apple", "h", "j", "n"}, -1, Color.Empty, Color.Lime, Nothing)
            Dim listViewItem4 As New ListViewItem(New String() {"Pear", "y", "u", "i"}, -1, Color.Empty, Color.FromArgb(CType(192, System.Byte), CType(128, System.Byte), CType(156, System.Byte)), Nothing)

            'Initialize the ListView control and add columns to it.
            Me.listView1 = New ListView

            ' Set the initial sorting type for the ListView.
            Me.listView1.Sorting = SortOrder.None
            ' Disable automatic sorting to enable manual sorting.
            Me.listView1.View = View.Details
            ' Add columns and set their text.
            Me.listView1.Columns.Add(New ColumnHeader)
            Me.listView1.Columns(0).Text = "Column 1"
            Me.listView1.Columns(0).Width = 100
            listView1.Columns.Add(New ColumnHeader)
            listView1.Columns(1).Text = "Column 2"
            listView1.Columns.Add(New ColumnHeader)
            listView1.Columns(2).Text = "Column 3"
            listView1.Columns.Add(New ColumnHeader)
            listView1.Columns(3).Text = "Column 4"
            ' Suspend control logic until form is done configuring form.
            ' Add Items to the ListView control.
            Me.listView1.Items.AddRange(New ListViewItem() {listViewItem1, listViewItem2, listViewItem3, listViewItem4})
            ' Set the location and size of the ListView control.
            Me.listView1.Location = New Point(10, 10)
            Me.listView1.Name = "listView1"
            Me.listView1.Size = New Size(300, 100)
            Me.listView1.TabIndex = 0
            ' Enable editing of the items in the ListView.
            Me.listView1.LabelEdit = True
            ' Connect the ListView.ColumnClick event to the ColumnClick event handler.
            AddHandler Me.listView1.ColumnClick, AddressOf ColumnClick

            ' Initialize the form.
            Me.ClientSize = New Size(400, 400)
            Me.Controls.AddRange(New Control() {Me.listView1})
            Me.Name = "ListViewSortForm"
            Me.Text = "Sorted ListView Control"
            ' Resume layout of the form.
        End Sub 'NewNew

        ' ColumnClick event handler.
        Private Sub ColumnClick(ByVal o As Object, ByVal e As ColumnClickEventArgs)
            ' Set the ListViewItemSorter property to a new ListViewItemComparer 
            ' object. Setting this property immediately sorts the 
            ' ListView using the ListViewItemComparer object.
            Me.listView1.ListViewItemSorter = New ListViewItemComparer(e.Column)
        End Sub

    End Class

    ' Implements the manual sorting of items by columns.
    Class ListViewItemComparer
        Implements IComparer

        Private col As Integer

        Public Sub New()
            col = 0
        End Sub

        Public Sub New(ByVal column As Integer)
            col = column
        End Sub

        Public Function Compare(ByVal x As Object, ByVal y As Object) As Integer _
           Implements IComparer.Compare
            Return [String].Compare(CType(x, ListViewItem).SubItems(col).Text, CType(y, ListViewItem).SubItems(col).Text)
        End Function
    End Class
End Namespace

.NET Framework
Available since 1.1
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