Ordering Columns in a List View

[Mick Dugan]

I know I can use the ascending and descending properties to order the first column in a list view, but how can I order the other columns as well?

[DiverDan]

Here's one that I've used for a while that seems to work fairly well for both alpha and numeric values.

 

In the ListViews ColumnClick event:

 

   Private Sub ListView1_ColumnClick(ByVal sender As Object, ByVal e As System.Windows.Forms.ColumnClickEventArgs) Handles ListView1.ColumnClick

       Dim bAltSort As Boolean = False
       Dim MySortClass As New SortClass()
       Try
           MySortClass.column = e.Column

           'Find out of we are sorting a numeric column
           If IsNumeric(ListView1.Items(0).SubItems(e.Column).Text.ToUpper.Trim) Then
               MySortClass.mNumeric = True
           Else
               MySortClass.mNumeric = False
           End If

           'Find out if the user is clicking on the same column.
           If mIntSelectedCol = e.Column Then
               MySortClass.AltSort = True
               mIntSelectedCol = -1
           Else
               mIntSelectedCol = e.Column
           End If

           ListView1.ListViewItemSorter = MySortClass

       Catch
           MessageBox.Show(Err.Description, "Sorting Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
       End Try
   End Sub

 

then the Sorter Class

 

   Private mIntSelectedCol As Integer

   Public Class SortClass
       Implements IComparer
       Private mColumn As Integer
       Public mNumeric As Boolean
       Private m_bAltSort As Boolean
       Public Property column() As Integer
           Get
               Return mColumn
           End Get
           Set(ByVal Value As Integer)
               mColumn = Value
           End Set
       End Property
       Public Property Numeric() As Boolean
           Get
               Return mNumeric
           End Get
           Set(ByVal Value As Boolean)
               mNumeric = Value
           End Set
       End Property
       Public Property AltSort() As Boolean
           Get
               Return m_bAltSort
           End Get
           Set(ByVal Value As Boolean)
               m_bAltSort = Value
           End Set
       End Property
       Public Function Compare(ByVal x As Object, ByVal y As Object) _
     As Integer Implements System.Collections.IComparer.Compare
           Dim lv1 As ListViewItem = x
           Dim lv2 As ListViewItem = y
           Try
               If mNumeric Then
                   If m_bAltSort = True Then
                       Return CLng(lv1.SubItems(mColumn).Text) + CDbl(lv2.SubItems(mColumn).Text)
                   Else
                       Return CDbl(lv2.SubItems(mColumn).Text) - CDbl(lv1.SubItems(mColumn).Text)
                   End If
               Else
                   If m_bAltSort = True Then
                       Return String.Compare(lv2.SubItems(mColumn).Text, lv1.SubItems(mColumn).Text)
                   Else
                       Return String.Compare(lv1.SubItems(mColumn).Text, lv2.SubItems(mColumn).Text)
                   End If
               End If
           Catch
           End Try
       End Function
   End Class

 

I think that this should work for you.

[kejpa]

Hey DiverDan

I just want to point out that you're having CLng along with CDbl when doing AltSort on numeric columns.

 

/Kejpa

[DiverDan]

Good point! Should be convert to double CDbl instead of convert to Long CLng.

 

Thanks,

Dan

[Mick Dugan]

Thanks!

 

Thanks for the feedback Dan!