I have a listbox with data as follows;
78550Item10
78550Item6
78550Item4
78550Item5
78550Item3
78550Item9
78550Item2
78550Item1
78550Item8
78550Item7How am I to sort the items in ascending order based on the digits at the end of the string so after sorting it is like;
78550Item1
78550Item2
78550Item3
78550Item4
78550Item5
78550Item6
78550Item7
78550Item8
78550Item9
78550Item10I dont even know how to start this one.
thnx n advance
Hi,
A ListBox with its Sorted set to true should not be bound to data using the DataSource property. To display sorted data in a bound ListBox, you should bind to a data source that supports sorting and have the data source provide the sorting.
Isnt it possible in any other way like taking the last digit and compare and sort according to the compare result?
If you have the listview in details view you can define a custom sort. Let's say your listview is called lvwList
lvwList.ListViewItemSorter = New MyCustomSorter
But first you have to write the MyCustomSorter class. This is code that will compare two of your items and determine whether one is <, =, or > to the other
Class MyCustomSorter
Implements IComparer
Public Function Compare(ByVal x As Object, ByVal y As Object) As Integer Implements System.Collections.IComparer.Compare
Dim item1, item2 As ListViewItem
Dim text1, text2 As String
item1 = CType(x, ListViewItem)
item2 = CType(y, ListViewItem)
text1 = item1.SubItems(0).Text.SubString(9)
text2 = item2.SubItems(0).Text.SubString(9)
If text1 > text2 Then Return 1
If text1 < text2 Then Return -1
Return 0
End FunctionIt's up to you to determine how to compare the items. I just did a substring as an example. You may have to get fancier to extract the strings. Also, for my example to work you would have to convert text1 and text2 to numeric and compare those.
Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Dim Strings() As String = {"78550Item10", "78550Item6", "78550Item4", "78550Item5", "78550Item3", "78550Item9", "78550Item2", "78550Item1", "78550Item8", "78550Item7"}
ListBox1.Items.AddRange(Strings)
SortListBox()
End Sub
Private Sub SortListBox()
'Uses linq to sort the box.
'Items must be in the format of xxxxxItemx
ListBox1.BeginUpdate()
'Create a copy of the listbox items
Dim Items(ListBox1.Items.Count - 1) As String
ListBox1.Items.CopyTo(Items, 0)
'Sort the items by the last digits
Dim Sorted = From Item In Items _
Order By CInt(CStr(Item).Substring(9)) Ascending
'Clear out the old and add the new
ListBox1.Items.Clear()
ListBox1.Items.AddRange(Sorted.ToArray)
ListBox1.EndUpdate()
End SubMake sure you have ListView1 in Details mode and that it has one (or more) columns in its collection.
Public Class Form1
Class MyCustomSorter
Implements IComparer
Public Function Compare(ByVal x As Object, ByVal y As Object) As Integer Implements System.Collections.IComparer.Compare
Dim item1 As ListViewItem = CType(x, ListViewItem)
Dim item2 As ListViewItem = CType(y, ListViewItem)
Dim num1 As Integer = Int(item1.SubItems(0).Text.Substring(9))
Dim num2 As Integer = Int(item2.SubItems(0).Text.Substring(9))
If num1 > num2 Then Return 1
If num1 < num2 Then Return -1
Return 0
End Function
End Class
Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Dim s As String
Dim strings() As String = {"78550Item10", "78550Item6", "78550Item4", "78550Item5", "78550Item3", "78550Item9", "78550Item2", "78550Item1", "78550Item8", "78550Item7"}
For Each s In strings
ListView1.Items.Add(s)
Next
ListView1.ListViewItemSorter = New MyCustomSorter
ListView1.Sorting = SortOrder.Ascending
End Sub
End Class@Reverend Jim. Thats a nice IComparer you got but I think hes talking about a ListBox and not a ListView.
I should also say If I were the poster I would change out the list box to a list view and use Reverend Jim's Prescription of the IComparer.
DOH! I do believe you are right. In my haste to help I overlooked that little fact. Ah well, as you so correctly stated, change ListBox to ListView and everything should work.
thanq guys, Reverend Jim's code did work when i changed to a listview, thank you all :)
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