asked on

Filter a combobox based on the other Combobox

Hello,

I have a windows form created in VB.Net with two combo box listing. I want the third combobox to filter the data based on the first two combo box
For example
First combo box: Category
Second Combo Box: Manufacturer
Third Combo Box: Model

On selection of the first two combobox, the third combo box should filter data.

Third combo box data source is from a table that holds all the three data. but display member is Model

How can it be done. please assist. Thank you

John (Yiannis) Toutountzoglou

Hi
All comboboxes are Databound?

John (Yiannis) Toutountzoglou

ok try this...

Private Sub ComboBox1_DropDownClosed(ByVal sender As Object, ByVal e As System.EventArgs) Handles ComboBox1.DropDownClosed
        Dim CustID As Integer = ComboBox1.SelectedValue
        ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
        Dim bs As New BindingSource
        bs.DataSource = Me.Combo3DataSet
        bs.DataMember = "MyCombobox3TableName"

        bs.Filter = ("Key_Model=" & CustID)

        Dim col As New ComboBox
        col = Me.ComboBox3

        col.DataSource = bs
        col.DisplayMember = "Model"
        col.ValueMember = "Key_Model"    '>>>>>For Example
    End Sub

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John (Yiannis) Toutountzoglou

CompleteCode...Because we have to check also the DropDown Event

Private Sub ComboBox1_DropDown(ByVal sender As Object, ByVal e As System.EventArgs) Handles ComboBox1.DropDown
        Try

            Dim CustID As Integer = Me.ComboBox1.SelectedValue
           


            ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
            Dim bs As New BindingSource
             bs.DataSource = Me.Combo3DataSet
        bs.DataMember = "MyCombobox3TableName"

             bs.Filter = ("Key_Model=" & CustID)

            Dim col As New ComboBox
            col = Me.ComboBox3

            col.DataSource = bs
            col.DisplayMember = "Model"
        col.ValueMember = "Key_Model"    '>>>>>For Example
            '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''



        Catch ex As InvalidCastException

        Catch ex As Exception

            MsgBox(ex.ToString)

        End Try
    End Sub

    Private Sub ComboBox1_DropDownClosed(ByVal sender As Object, ByVal e As System.EventArgs) Handles ComboBox1.DropDownClosed
        ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
        Dim bs As New BindingSource
        bs.DataSource = Me.Combo3DataSet
        bs.DataMember = "MyCombobox3TableName"

        bs.Filter = ("Key_Model=" & CustID)

        Dim col As New ComboBox
        col = Me.ComboBox3

        col.DataSource = bs
        col.DisplayMember = "Model"
        col.ValueMember = "Key_Model"    '>>>>>For Example
    End Sub

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ASKER CERTIFIED SOLUTION

Éric Moreau

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angel7170

ASKER

I tried this code with modifications but doesn't seem working. I have also attached the sreenshot of what I see in the model combo box...
Please assist.

Private Sub cmb_Category_DropDown(ByVal sender As Object, ByVal e As System.EventArgs) Handles cmb_Category.DropDown
        Try
            Dim Category As String = cmb_Category.Text
            Dim Manu As String = cmb_Manufacturer.Text
            ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
            Dim bs As New BindingSource
            bs.DataSource = Me.TBLMODELBindingSource
            bs.DataMember = "MODEL"

            bs.Filter = ("MODEL like '" + Category + "'")

            Dim col As New ComboBox
            col = Me.cmb_Model

            col.DataSource = bs
            col.DisplayMember = "MODEL"
            'col.ValueMember = "MODEL"    '>>>>>For Example
        Catch ex As InvalidCastException

        Catch ex As Exception

            MsgBox(ex.ToString)

        End Try

    End Sub

    Private Sub cmb_Category_DropDownClosed(ByVal sender As Object, ByVal e As System.EventArgs) Handles cmb_Category.DropDownClosed
        Dim Category As String = cmb_Category.Text
        Dim Manu As String = cmb_Manufacturer.Text
        ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
        Dim bs As New BindingSource
        bs.DataSource = Me.TBLMODELBindingSource
        bs.DataMember = "MODEL"

        bs.Filter = ("MODEL like '" + Category + "'")

        Dim col As New ComboBox
        col = Me.cmb_Model

        col.DataSource = bs
        col.DisplayMember = "MODEL"
        'col.ValueMember = "MODEL"    '>>>>>For Example

    End Sub

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test.doc

John (Yiannis) Toutountzoglou

just a note:
in your form load set :
Me.Combo1DataSet.EnforceConstraints = False 'Combo1DataSet is the name of your dataset in combobox1
Me.Combo3DataSet.EnforceConstraints = False ''Combo2DataSet is the name of your dataset in combobox2

Also
"MyCombobox3TableName" is the table or query ,the one you create the dataset which is bounded in combobox3

try it and you'll see ..it works fine...

John (Yiannis) Toutountzoglou

try to use selected value with the value member and amke the filter as my code.

John (Yiannis) Toutountzoglou

col.DisplayMember = "MODEL"
'col.ValueMember = "MODEL" ?? why the same?

John (Yiannis) Toutountzoglou

try this

Private Sub cmb_Category_DropDown(ByVal sender As Object, ByVal e As System.EventArgs) Handles cmb_Category.DropDown
        Try
            Dim Category As String = cmb_Category.SelectedValue
            Dim Manu As  = cmb_Manufacturer.Text
            ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
            Dim bs As New BindingSource
            bs.DataSource = Me.TBLMODELBindingSource
            bs.DataMember = "MODEL"

            bs.Filter = ("Model=" & Category) 

            Dim col As New ComboBox
            col = Me.cmb_Model

            col.DataSource = bs
            col.DisplayMember = "MODEL"
            'col.ValueMember = "MODEL"    '>>>>>For Example
        Catch ex As InvalidCastException

        Catch ex As Exception

            MsgBox(ex.ToString)

        End Try

    End Sub

    Private Sub cmb_Category_DropDownClosed(ByVal sender As Object, ByVal e As System.EventArgs) Handles cmb_Category.DropDownClosed
        Dim Category As String = cmb_Category.Text
        Dim Manu As String = cmb_Manufacturer.SelectedValue
        ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
        Dim bs As New BindingSource
        bs.DataSource = Me.TBLMODELBindingSource
        bs.DataMember = "MODEL"

       bs.Filter = ("Model=" & Category) 

        Dim col As New ComboBox
        col = Me.cmb_Model

        col.DataSource = bs
        col.DisplayMember = "MODEL"
        'col.ValueMember = "MODEL"    '>>>>>For Example

    End Sub

Open in new window

angel7170

ASKER

There is no option for EnforseConstraints...My combo boxes are bound to Binding source.

Me.Combo1DataSet.EnforceConstraints = False 'Combo1DataSet is the name of your dataset in combobox1
Me.Combo3DataSet.EnforceConstraints = False ''Combo2DataSet is the name of your dataset in combobox2

Éric Moreau

have you checked my article?

John (Yiannis) Toutountzoglou

did you try the alst post?
it works perfect on me.
@emoreau Could you please post a link?

John (Yiannis) Toutountzoglou

@angel7170
Can you post both DisplayMember and ValueMember from ComboBox1 and 3?

Éric Moreau

>>@emoreau Could you please post a link?
see post 33737131

John (Yiannis) Toutountzoglou

OOOOhhhh ... sorry ...i didn't Scroll up the page...

John (Yiannis) Toutountzoglou

Slightly Close...@emoreau my post Works (Slightly Close to yours)...But Your Article is Perfect..The only thing i have to do is to quit the Question...
@angel7170 read this article..there is more analysis..and you'll understand better what is going on ...!!thanks @emoreau i will keep the code too...!!

angel7170

ASKER

ok, thank you ..both. I didn't get a chance to read through the article...but will do so.. thanks again.