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David L. HansenFlag for United States of America

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How can I implement autocompletion in a combobox that has a generic list as its datasource?

I've created a generic list (a collection) and made it the dataSource for my combobox.  
Now I need to use autocompletion for when the user begins to type in the combobox while searching for something in the list.  There seems to be a good amount of help on the web for autocompletion where the combobox has a different kind of datasource (ie. datatable) but I'm still scratching my head trying to get this to work with a generic list.  

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A generic list of what? Strings? Custom objects?
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Custom objects.  Each item (object) has several properties and methods.  The collection object which holds these items uses the System.ComponentModel.BindingList(Of T) where T is my custom object.
The collection object is the combobox's datasource.
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Ahh Monday, back to work.  BTW, thanks for your help on this.

So, when I use:
this.comboBox1.AutoCompleteSource = AutoCompleteSource.ListItems;

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I get the following error - "Value of type 'System.Windows.Forms.AutoCompleteSource' cannot be converted to 'System.Windows.Forms.AutoCompleteStringCollection'.
Can you post your implementation? The code I posted was a working sample.
Sure, here it is:
Private Sub frmOfficiant_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        Officiants = New Officiants
        Dim blankOfficiant As New Officiant 'this is provided for the user to add a new officiant if need be
        Officiants.Insert(0, blankofficiant)

        With Me.cboOfficiantLastName
            .DataSource = Officiants
            .DisplayMember = "LastName"
            .AutoCompleteMode = AutoCompleteMode.SuggestAppend
            .AutoCompleteCustomSource = AutoCompleteSource.ListItems
        End With

End Sub


Public Class Officiants
    Inherits System.ComponentModel.BindingList(Of Officiant)

    'the following three subs allow this class to know when a 
    'new item is inserted, added, or the list is changed. 
    Protected Overrides Sub InsertItem(ByVal index As Integer, ByVal item As Officiant)
        MyBase.InsertItem(index, item)
    End Sub

    Protected Overrides Sub OnAddingNew(ByVal e As System.ComponentModel.AddingNewEventArgs)
    End Sub

    Protected Overrides Sub OnListChanged(ByVal e As System.ComponentModel.ListChangedEventArgs)
    End Sub

    Public Sub RefreshFromDatabase()

        Dim strsql As String = _
            "SELECT officiant_id, title, first_name, " & _
            " last_name, address1, address2, " & _
            " city, state, zip, " & _
            " phone " & _
            "FROM Officiant " & _
            "--where --ADD WHERE STATEMENT HERE "

        Dim drItems As SqlClient.SqlDataReader
        drItems = DataSrc.GetDataReader(strsql)

        'clear current list 

        'cycle through all items and add to list 
        While drItems.Read
            Dim x As New Officiant
            x.OfficiantId = CInt(NullToZero(drItems("officiant_id")))
            x.Title = CStr(NullToBlank(drItems("title")))
            x.FirstName = CStr(NullToBlank(drItems("first_name")))
            x.LastName = CStr(NullToBlank(drItems("last_name")))
            x.Address1 = CStr(NullToBlank(drItems("address1")))
            x.Address2 = CStr(NullToBlank(drItems("address2")))
            x.City = CStr(NullToBlank(drItems("city")))
            x.State = CStr(NullToBlank(drItems("state")))
            x.Zip = CStr(NullToBlank(drItems("zip")))
            x.Phone = CStr(NullToBlank(drItems("phone")))
        End While

        'close the datareader 

    End Sub


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Finally found the issue!  I had:
 .AutoCompleteCustomSource = AutoCompleteSource.ListItems

instead of:
.AutoCompleteSource = AutoCompleteSource.ListItems

I just couldn't see the difference even though it was right there in front of me.