[Solved] BindingSource.Find Error: Specified method is not supported

Hi kana250688,

Refer the following code to fing the index of the selected product.

Use ToList method to find the Product and then IndexOf method of BindingSource to get the index value.

Code

Imports System.ComponentModel

Public Class Form1
    Private OrderDetail As List(Of OrderDetail)
    Private bindingSource As BindingSource = Nothing
    Private selectedOrder As String = "TEST 3000"
    Private selectedIndex As Integer

    Public Sub New()
        InitializeComponent()
        Me.CenterToScreen()
    End Sub

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        Me.LoadData()
    End Sub

    Private Sub LoadData()
        OrderDetail = New List(Of OrderDetail) From {
            New OrderDetail() With {
                .Invono = "PI0001",
                .InvoDate = Convert.ToDateTime("06-05-2024"),
                .Days = Convert.ToDateTime("06-05-2024").ToString("dddd"),
                .ProductName = "TEST 1000",
                .UnitPrice = 15000,
                .Quantity = 20
            },
            New OrderDetail() With {
                .Invono = "PI0002",
                .InvoDate = Convert.ToDateTime("07-05-2024"),
                .Days = Convert.ToDateTime("07-05-2024").ToString("dddd"),
                .ProductName = "TEST 2000",
                .UnitPrice = 25000,
                .Quantity = 20
            },
            New OrderDetail() With {
                .Invono = "PI0003",
                .InvoDate = Convert.ToDateTime("06-05-2024"),
                .Days = Convert.ToDateTime("06-05-2024").ToString("dddd"),
                .ProductName = "TEST 3000",
                .UnitPrice = 17000,
                .Quantity = 20
            },
            New OrderDetail() With {
                .Invono = "PI0004",
                .InvoDate = Convert.ToDateTime("07-05-2024"),
                .Days = Convert.ToDateTime("07-05-2024").ToString("dddd"),
                .ProductName = "TEST 4000",
                .UnitPrice = 18000,
                .Quantity = 20
            },
               New OrderDetail() With {
                .Invono = "PI0005",
                .InvoDate = Convert.ToDateTime("06-05-2024"),
                .Days = Convert.ToDateTime("06-05-2024").ToString("dddd"),
                .ProductName = "TEST 5000",
                .UnitPrice = 19000,
                .Quantity = 20
            }
        }

        bindingSource = New BindingSource With {.DataSource = New BindingList(Of OrderDetail)(CType(OrderDetail, IList(Of OrderDetail)))}
        DataGridView1.DataSource = bindingSource
        DataGridView1.AutoResizeColumns(DataGridViewAutoSizeColumnsMode.AllCells)
    End Sub

    Private Sub DataGridView1_SelectionChanged(sender As Object, e As EventArgs) Handles DataGridView1.SelectionChanged
        If (DataGridView1.SelectedRows.Count > 0) Then
            selectedOrder = DataGridView1.SelectedRows(0).Cells("ProductName").Value.ToString
        End If
    End Sub

    Private Sub DataGridView1_DataBindingComplete(sender As Object, e As DataGridViewBindingCompleteEventArgs) Handles DataGridView1.DataBindingComplete
        If (Not String.IsNullOrEmpty(selectedOrder) AndAlso (e.ListChangedType = ListChangedType.Reset)) Then
            If (bindingSource.List.Count > 0) Then
                'error below line code
                Dim obj = bindingSource.List.OfType(Of OrderDetail)().ToList().Find(Function(f) f.ProductName = selectedOrder)
                selectedIndex = bindingSource.IndexOf(obj)
                If (selectedIndex <= 0) Then
                    selectedIndex = 0
                End If

                DataGridView1.Rows(selectedIndex).Selected = True
            Else
                selectedOrder = String.Empty
            End If
        End If
    End Sub
End Class

Public Class OrderDetail
    Public Property Invono As String
    Public Property InvoDate As DateTime
    Public Property Days As String
    Public Property ProductName As String
    Public Property UnitPrice As Integer
    Public Property Quantity As Integer
End Class

Screenshots

Selected Index

Selected DataGridViewRow