Question Datagridview combobox / datagridview it self data binding ( Error System.format exce

[Aralimara]

Good evening every body :cheerful:
my post is having a reference to jmcillhenny writings here + other links

i am doing like this

(1) put 3 bindingsource controls on form
(3) binded to different dataset -> datatables ( untyped )
(3) binded the combobox column of the datagridview to binding sources
(4) at the last i have set the data property + datasource of the datagridview ( manually created the columns autogenerate columns is set to false )

now the bug says that

here are my code details

Private Sub BindGridCombo_Depots()

        Dim SQL_bind = <sql>SELECT
stationregistry.StationName as CrewDepot,
depot_config.DepotId
FROM
stationregistry
INNER JOIN depot_config ON stationregistry.StationId = depot_config.StationId_Fk
WHERE stationregistry.CrewBase = "Y"
;
</sql>
        Dim S As String = SQL_bind.Value.ToString
        Dim Cnn896 As New MySqlConnection
        Dim Cmd896 As New MySqlCommand(S, Cnn896)
        Dim Da896 As New MySqlDataAdapter(Cmd896)
        Dim Ds896 As New DataSet

        Dim Cnm As New ConnectionManager
        Cnm.InitializeConnectionProperty(Cs)

        Dim Dt_Sepot As New DataTable

        With Da896
            Cnm.Connect(Cnn896)
            .Fill(Ds896, "Container")
            Cnm.DisConnect(Cnn896)
            .Dispose()
            Cmd896.Dispose()
        End With

        Dt_Sepot = Ds896.Tables("Container")
        Ds896.Dispose()

        With Me.Depot_Source
            .DataSource = Dt_Sepot
        End With

        With Me.Dgv_CrewDetail

            Me.DepotCombo.DataPropertyName = "StationName"
            Me.DepotCombo.DisplayMember = "CrewDepot"
            Me.DepotCombo.ValueMember = "DepotId".ToString()
            Me.DepotCombo.DataSource = Depot_Source
            Me.DepotCombo.ValueType = GetType(String)

        End With
    End Sub

Private Sub BindGridCombo_Li()

        Dim SQL_bind = <sql>SELECT
lidata.LiId,lidata.LIname as CrewLiname
FROM
lidata
WHERE
lidata.Discontinue = "N"
;
</sql>
        Dim S As String = SQL_bind.Value.ToString
        Dim Cnn896 As New MySqlConnection
        Dim Cmd896 As New MySqlCommand(S, Cnn896)
        Dim Da896 As New MySqlDataAdapter(Cmd896)
        Dim Ds896 As New DataSet

        Dim Cnm As New ConnectionManager
        Cnm.InitializeConnectionProperty(Cs)

        Dim Dt_Li As New DataTable

        With Da896
            Cnm.Connect(Cnn896)
            .Fill(Ds896, "Container")
            Cnm.DisConnect(Cnn896)
            .Dispose()
            Cmd896.Dispose()
        End With

        Dt_Li = Ds896.Tables("Container")
        Ds896.Dispose()

        With Me.LI_source
            .DataSource = Dt_Li
        End With

        With Me.Dgv_CrewDetail

            Me.NLIcombo.DataPropertyName = "LIname"
            Me.NLIcombo.DisplayMember = "CrewLiname"
            Me.NLIcombo.ValueMember = "LIid".ToString()
            Me.NLIcombo.DataSource = LI_source
            Me.NLIcombo.ValueType = GetType(String)

        End With


    End Sub

 Private Sub Bind_FullGrid()

        Dim SQL_bind = <sql>SELECT
crewregistry.CrewName,
crewregistry.Designation,
stationregistry.StationName,
crewregistry.CugNumber,
crewregistry.PerNumber,
crewregistry.CRISid,
lidata.LIname,
crewregistry.Inactive,
crewregistry.CrewId
FROM
crewregistry
INNER JOIN depot_config ON crewregistry.CrewBaseId_Fk = depot_config.DepotId
INNER JOIN stationregistry ON depot_config.StationId_Fk = stationregistry.StationId
INNER JOIN lidata ON crewregistry.NliId_Fk = lidata.LiId;
</sql>


        Dim S As String = SQL_bind.Value.ToString
        Dim Cnn896 As New MySqlConnection
        Dim Cmd896 As New MySqlCommand(S, Cnn896)
        Dim Da896 As New MySqlDataAdapter(Cmd896)
        Dim Ds896 As New DataSet

        Dim Cnm As New ConnectionManager
        Cnm.InitializeConnectionProperty(Cs)

        Dim Dt_FullGrid As New DataTable

        With Da896
            Cnm.Connect(Cnn896)
            .Fill(Ds896, "Container")
            Cnm.DisConnect(Cnn896)
            .Dispose()
            Cmd896.Dispose()
        End With

        Dt_FullGrid = Ds896.Tables("Container")
        Ds896.Dispose()

        With Me.S_fullGridBiner
            .DataSource = Dt_FullGrid
        End With

        With Me.Dgv_CrewDetail
            .DataSource = S_fullGridBiner
        End With

    End Sub

Private Sub CrewBiodata_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        Me.Dgv_CrewDetail.AutoGenerateColumns = False '' Columns + DataProperty name of columns set at design time
        Me.Dgv_CrewDetail.AllowUserToAddRows = True



        Call BindGridCombo_Depots() '' 
        Call BindGridCombo_Li() '' Bind another combobox column
        Call Bind_FullGrid() ''  data property of the columns are set in design time

    End Sub

 

[Aralimara]

I found that if i Comment out the line which sets the value member
i am not getting the bug , that is

' Me.NLIcombo.ValueMember = "LIid"
         '  Me.DepotCombo.ValueMember = "DepotId"

but desparatly i need the valuemember because i need the selected value of combo
how to do it please

 

[Aralimara]

to some extent i found solutions

(1) in dataerror event i set the

e.throwexception = false

(2) i my SQL statement i set the value member casted to varchar like

CAST(depot_config.DepotId AS Char) as DepotId

now ok working ok , but i don't think so that this is the right way to handle this issue

 

[Aralimara]

Please have a look at this link please

i had a question 2 days back , i think i wrongly posted at MySQL forum instead of vb.net forms
it is in connection with the datagridview combo box column ,