I-BEGO

oom oom minta pencerahannya,saya menampilkan data di lsit view dg code :

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Private Sub IsiListView()
        With ListView1
            .Items.Clear()
            .Columns.Clear()
            .Columns.Add("No", 70, HorizontalAlignment.Left)
            .Columns.Add("Account", 80, HorizontalAlignment.Left)
            .Columns.Add("AccDesc", 150, HorizontalAlignment.Left)
            .Columns.Add("Segment ", 70, HorizontalAlignment.Left)
            .Columns.Add("SegmentDesc ", 150, HorizontalAlignment.Left)
            .Columns.Add("CostCenter", 80, HorizontalAlignment.Left)
            .Columns.Add("CostCenDesc", 150, HorizontalAlignment.Left)
            .Columns.Add("GabCode", 80, HorizontalAlignment.Left)
            .Columns.Add("Grouping1 ", 100, HorizontalAlignment.Left)
            .Columns.Add("Grouping2", 100, HorizontalAlignment.Left)
            .Columns.Add("Grouping3", 100, HorizontalAlignment.Left)
            .Columns.Add("Grouping4", 100, HorizontalAlignment.Left)
        End With

        qSelect = " SELECT * " _
                    & " FROM t_key " _
                    & " ORDER BY Account "

        command = New SqlCommand(qSelect, Koneksi.Koneksi)
        reader = command.ExecuteReader
        no = 0
        Do While reader.Read
            no = no + 1
            Dim myItem As New ListViewItem(no & ".")
            myItem.SubItems.Add(reader.Item("Account"))
            myItem.SubItems.Add(reader.Item("AccDesc"))
            myItem.SubItems.Add(reader.Item("Segment"))
            myItem.SubItems.Add(reader.Item("SegmentDesc"))
            myItem.SubItems.Add(reader.Item("CostCenter"))
            myItem.SubItems.Add(reader.Item("CostCenDesc"))
            myItem.SubItems.Add(reader.Item("GabCode"))
            myItem.SubItems.Add(reader.Item("Groping1"))
            myItem.SubItems.Add(reader.Item("Groping2"))
            myItem.SubItems.Add(reader.Item("Groping3"))
            myItem.SubItems.Add(reader.Item("Groping4"))
            ListView1.Items.Add(myItem)
        Loop

    End Sub

tp ketika ada data yg kosong akan error seperti di bawah :

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System.Reflection.AmbiguousMatchException was unhandled by user code
  Message=Overload resolution failed because no Public 'Add' can be called with these arguments:
    'Public Function Add(text As String) As System.Windows.Forms.ListViewItem.ListViewSubItem':
        Argument matching parameter 'text' cannot convert from 'DBNull' to 'String'.
    'Public Function Add(item As System.Windows.Forms.ListViewItem.ListViewSubItem) As System.Windows.Forms.ListViewItem.ListViewSubItem':
        Argument matching parameter 'item' cannot convert from 'DBNull' to 'ListViewSubItem'.
  Source=Microsoft.VisualBasic
  StackTrace:
       at Microsoft.VisualBasic.CompilerServices.OverloadResolution.ResolveOverloadedCall(String MethodName, List`1 Candidates, Object[] Arguments, String[] ArgumentNames, Type[] TypeArguments, BindingFlags LookupFlags, Boolean ReportErrors, ResolutionFailure& Failure)
       at Microsoft.VisualBasic.CompilerServices.OverloadResolution.ResolveOverloadedCall(String MethodName, MemberInfo[] Members, Object[] Arguments, String[] ArgumentNames, Type[] TypeArguments, BindingFlags LookupFlags, Boolean ReportErrors, ResolutionFailure& Failure)
       at Microsoft.VisualBasic.CompilerServices.NewLateBinding.ResolveCall(Container BaseReference, String MethodName, MemberInfo[] Members, Object[] Arguments, String[] ArgumentNames, Type[] TypeArguments, BindingFlags LookupFlags, Boolean ReportErrors, ResolutionFailure& Failure)
       at Microsoft.VisualBasic.CompilerServices.NewLateBinding.CallMethod(Container BaseReference, String MethodName, Object[] Arguments, String[] ArgumentNames, Type[] TypeArguments, Boolean[] CopyBack, BindingFlags InvocationFlags, Boolean ReportErrors, ResolutionFailure& Failure)
       at Microsoft.VisualBasic.CompilerServices.NewLateBinding.ObjectLateCall(Object Instance, Type Type, String MemberName, Object[] Arguments, String[] ArgumentNames, Type[] TypeArguments, Boolean[] CopyBack, Boolean IgnoreReturn)
       at Microsoft.VisualBasic.CompilerServices.NewLateBinding.LateCall(Object Instance, Type Type, String MemberName, Object[] Arguments, String[] ArgumentNames, Type[] TypeArguments, Boolean[] CopyBack, Boolean IgnoreReturn)
       at Acc_Grouping.FormMasterGrouping.IsiListView() in F:\2945\Vb All\vs2010\Account Grouping\Acc Grouping\FormMasterGrouping.vb:line 65
       at Acc_Grouping.FormMasterGrouping.FormMasterGrouping_Load(Object sender, EventArgs e) in F:\2945\Vb All\vs2010\Account Grouping\Acc Grouping\FormMasterGrouping.vb:line 263
       at System.Windows.Forms.Form.OnLoad(EventArgs e)
       at System.Windows.Forms.Form.OnCreateControl()
       at System.Windows.Forms.Control.CreateControl(Boolean fIgnoreVisible)
       at System.Windows.Forms.Control.CreateControl()
       at System.Windows.Forms.Control.SetVisibleCore(Boolean value)
  InnerException:

terima kasih oom oom sebelum nya!!

Ada dua cara untuk menghindarkan error seperti itu:
a. Membuat perintah query sedemikian rupa sehingga tidak ada null value yang dikembalikan
contoh:

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SELECT Account,  ISNULL(AccDesc, '') AS AccDesc, ISNULL(GabCode,'--MISSING--') as GabCode
FROM Account


Jadi nggak bakal ada null value dari hasil querynya. Catatan: kode di atas untuk ms sql server; untuk database lainnya mungkin fungsi pengecekan nilai null berbeda.

b. Melakukan pengecekan data sebelum ditampilkan:

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...
            myItem.SubItems.Add(If reader.Item("Account") = dbnull.value then "" else reader.item("Account").toString() )
...


Hatun Nuhun Pisan ath oom,ilmu baru buat saya,saya pilih yg view di sql server nya saja.
thanks sekali lagi

aku tambahkan aja ya
bisa juga pake fungsi iif klo tlu panjang pake if _ then _ else _ end if

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mItem.SubItem.Add(iif(IsDBNull(reader.Item("Account")),"",reader.Item("Account")))