Use DataTable select with multi CheckBox in DataGridView in VB.Net

Dear Sir,

I'm Trying to use datatable select when the criteria are the same with multi checkbox in datagridview and just add the quantity in the vb.net.

Please Guide me.

Thanks

If I use a single checkbox then the result is appropriate, below I attach the video link

result from code 22062024

Code in form1

Public Class Form1
    Private table1 As New DataTable
    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load

        table1.Columns.Add(New DataColumn("Column1", GetType(String)))
        table1.Columns.Add(New DataColumn("Column2", GetType(String)))
        table1.Columns.Add(New DataColumn("Column3", GetType(String)))
        table1.Columns.Add(New DataColumn("Column4", GetType(String)))
        table1.Columns.Add(New DataColumn("Qty", GetType(Integer)))
        DataGridView1.DataSource = table1
    End Sub
    Private Sub BTNAdd_Click(sender As Object, e As EventArgs) Handles BTNAdd.Click
        Dim Column2 As String = TextBox2.Text.Trim()
        Dim Column1 = TextBox1.Text.Trim()
        Using frm = New Form2(Column2)

            If frm.ShowDialog() = DialogResult.OK Then
                Dim datarow As DataRow = Nothing
                Dim Column3 = frm.DataGridView1.CurrentRow.Cells(3).Value?.ToString()
                Dim Column4 = frm.DataGridView1.CurrentRow.Cells(4).Value?.ToString()
                If table1.Rows.Cast(Of DataRow).Any() Then
                    datarow = table1.Select($"Column1 = '{Column1}' AND Column2 = '{Column2}' AND Column3 = '{Column3}' AND Column4 = '{Column4}'").FirstOrDefault()
                End If
                If datarow IsNot Nothing Then
                    'Dim qty = If(datarow("Qty") Is Nothing, 0, datarow.Field(Of Integer)("Qty"))
                    Dim qty = If(datarow("Qty") Is DBNull.Value, 0, datarow.Field(Of Integer)("Qty"))
                    datarow.SetField("Qty", Qty + 1)
                    Return
                Else
                End If
                Try
                    For Each row2 As DataGridViewRow In frm.DataGridView1.Rows
                        Dim isselect As Boolean = Convert.ToBoolean(row2.Cells("checkboxcolumn").Value)
                        If isselect Then
                            table1.Rows.Add(Column1, Column2, Column3, Column4, 1)
                            TextBox1.Clear()
                            TextBox2.Clear()
                        End If
                    Next
                Catch ex As Exception
                    MessageBox.Show(ex.Message)
                End Try
            Else

                Return
            End If
        End Using
    End Sub
End Class

Code in form2

Public Class Form2
    Sub New()
        InitializeComponent()
    End Sub
 Public Sub New(Column2 As String)
        Me.New
        Dim table2 As New DataTable("Players")
        table2.Columns.Add(New DataColumn("Column1", GetType(String)))
        table2.Columns.Add(New DataColumn("Column2", GetType(String)))
        table2.Columns.Add(New DataColumn("Column3", GetType(String)))
        table2.Columns.Add(New DataColumn("Column4", GetType(String)))
        table2.Rows.Add("001", "TEST1", "TEST1", "TEST1")
        table2.Rows.Add("001", "TEST1", "TEST1", "-")
        table2.Rows.Add("001", "TEST1", "-", "-")
        table2.Rows.Add("001", "TEST1", "-", "TEST1")
        table2.Rows.Add("002", "TEST2", "-", "TEST2")
        DataGridView1.DataSource = table2
        Dim CheckedBoxColumn As New DataGridViewCheckBoxColumn
        CheckedBoxColumn.Width = 40
        CheckedBoxColumn.Name = "checkboxcolumn"
        CheckedBoxColumn.HeaderText = "Check"
        DataGridView1.Columns.Insert(0, CheckedBoxColumn)
    End Sub

    Private Sub BtnOK_Click(sender As Object, e As EventArgs) Handles BtnOK.Click
        DialogResult = DialogResult.OK
    End Sub
End Class

So when I try textbox1 : 001 and textbox2 : TEST1

the result should be as below :

First Result

Column1 Column2    Column3  Column4 Qty

001          TEST1      TEST1    TEST1    1

001          TEST1      TEST1       -        1 

001          TEST1         -           -         1

001          TEST1         -           TEST1  1

Second Result

Column1 Column2    Column3 Column4 Qty

001          TEST1      TEST1    TEST1  2

001          TEST1      TEST1       -      2 

001          TEST1         -           -       2

001          TEST1         -          TEST1 2