Sort a Custom Class Collection in VB6

KeithF

Hi Folks, I am having difficulty sorting a custom class based collection on two fields and am wondering if anyone can assist me. I have a class that looks like so:

Class myClass

private ID as String
private Name as String
private TK as String
private Di as String
private M as String

End Class

Using this class i add to a Collection a number of items, e.g.

Private colClass As Collection
Private clsTheClass As myClass

Set colClass = New Collection

Set clsTheClass = New myClass
clsTheClass.Name = "A"
clsTheClass.TKs = "100"
clsTheClass.Di = "5"
clsTheClass.ID = "1"
clsTheClass.M = "9"

colClass.Add clsTheClass

What i end up with it is a collection that looks like so after adding all the items:

ID |Name |TK |Di |M
1 A 100 5 9
2 B 100 3 9
3 C 10 5 9
4 D 10 7 9
5 E 10 1 9
6 F 400 9 5
7 F 400 4 5

I need to sort the collection On TK, and then DI. That should make the collection look like this:

ID |Name |TK |Di |M
6 F 400 9 5
7 F 400 4 5
1 A 100 5 9
2 B 100 3 9
4 D 10 7 9
3 C 10 5 9
5 E 10 1 9

I am currently using this method to sort on TK, but i cannot get it to work how i need the output:

Public Sub SortCollection(ColVar As Collection)
Dim oCol As Collection
Dim i As Integer
Dim i2 As Integer
Dim iBefore As Integer

If Not (ColVar Is Nothing) Then

    If ColVar.Count > 0 Then
    
        Set oCol = New Collection
        
        For i = 1 To ColVar.Count
        
            If oCol.Count = 0 Then
                oCol.Add ColVar(i)
            Else
                iBefore = 0
                
                For i2 = oCol.Count To 1 Step -1
                
                    If CLng(ColVar(i).TK) < CLng(oCol(i2).TK) Then
                        iBefore = i2
                    Else
                        Exit For
                    End If
                    
                Next
                
                If iBefore = 0 Then
                    oCol.Add ColVar(i)
                Else
                    oCol.Add ColVar(i), , iBefore
                End If

_Marshall

Hi Keith Is it known how many elements are added to the collection or is that defined at runtime?

PrissySC

Whenever I sort, I find the largest, or the least first and set the value to "x". From there I work up, or down assigning to a temp object, collection or array, and replacing "x" as the largest each time. For example, x = 0 for each item in collection if item > x then x = item end if next This gets the largest to begin. tempCollection.add(x) while tempcollection.count isnot collection.count for each item in collection set x if the item is less than the last in tempcollection and is not less than x next tempcollection.add(x) loop That is a level one sort, but you should be able to expand to code easily enough. Sorry that I lack any time, or I would have done it for you!

Roy Heil

You could implement the IComparable interface in your class, and then define the CompareTo function. Put your comparison logic in this CompareTo function. Then all you would need to do is call the Sort method on your collection. MyNewCol.Sort()

Roy.