DataTable.Rows.Count always returns 0 - VB.NET - vb.net

Question

I'm trying to populate DataGridView cells with information from two (parent, child tables). Everything works just fine, except for this part table.Rows.Count. It always returns 0, no matter that I have one record in the table.
This is the code:
Private Sub Query__tbl_purchase_order_articlesDataGridView_CellEndEdit(sender As Object, e As DataGridViewCellEventArgs) Handles Query__tbl_purchase_order_articlesDataGridView.CellEndEdit
Dim table As DataTable = Orders_DBDataSet.Tables("tbl_list_of_articles")
Dim selectedRowCount As Integer = Query__tbl_purchase_order_articlesDataGridView.CurrentCell.RowIndex
Dim art_ID As Integer = CInt(Query__tbl_purchase_order_articlesDataGridView.Rows(selectedRowCount).Cells(0).Value)
Dim art_ttl As String
Dim art_ttl_tr As String
Dim mu As String
Dim art_ttl_i As Integer
Dim art_ttl_tr_i As Integer
Dim mu_i As Integer
Dim art_ID_t_i As Integer
Dim art_ttl_t_i As Integer
Dim art_ttl_tr_t_i As Integer
Dim mu_t_i As Integer
Dim i As Integer
'search for column index in DataGridView
For i = 0 To Query__tbl_purchase_order_articlesDataGridView.Columns.Count - 1
If Query__tbl_purchase_order_articlesDataGridView.Columns(i).HeaderText.ToString = "article_name" Then
art_ttl_i = i
End If
If Query__tbl_purchase_order_articlesDataGridView.Columns(i).HeaderText.ToString = "article_name_tr" Then
art_ttl_tr_i = i
End If
If Query__tbl_purchase_order_articlesDataGridView.Columns(i).HeaderText.ToString = "masurement_unit" Then
mu_i = i
End If
Next
'search for column index in "table"
For i = 0 To table.Columns.Count - 1
If table.Columns(i).ColumnName.ToString = "article_ID" Then
art_ID_t_i = i
End If
If table.Columns(i).ColumnName.ToString = "article_name" Then
art_ttl_t_i = i
End If
If table.Columns(i).ColumnName.ToString = "article_name_tr" Then
art_ttl_tr_t_i = i
End If
If table.Columns(i).ColumnName.ToString = "masurement_unit" Then
mu_t_i = i
End If
Next
For i = 0 To table.Rows.Count
If art_ID = CInt(table.Rows(i).Item(art_ID_t_i).ToString()) Then
art_ttl = table.Rows(i).Item(art_ttl_t_i).ToString()
art_ttl_tr = table.Rows(i).Item(art_ttl_tr_t_i).ToString()
mu = table.Rows(i).Item(mu_t_i).ToString()
Query__tbl_purchase_order_articlesDataGridView.Rows(selectedRowCount).Cells(art_ttl_i).Value = art_ttl
Query__tbl_purchase_order_articlesDataGridView.Rows(selectedRowCount).Cells(art_ttl_tr_i).Value = art_ttl_tr
Query__tbl_purchase_order_articlesDataGridView.Rows(selectedRowCount).Cells(mu_i).Value = mu
Exit For
End If
Next
End Sub
Also, I tied to test it like this, but the result is the same. It can find a table index, but always return 0 as a table row count.
'test ========================================
Dim x, y As Integer
For x = 0 To Orders_DBDataSet.Tables.Count - 1
If Orders_DBDataSet.Tables(x).TableName.ToString = "tbl_list_of_articles" Then
y = x
End If
Next
x = 0
For Each row As DataRow In table.Rows
x = x + 1
Next
'============================================
x = Orders_DBDataSet.Tables(y).Rows.Count

Answer 1

Most of the times this happened to me because I was not actually using the instance of the dataset "connected" to the form. What does this mean? You either don't populate the dataset instance tied to the form in the Load event, or you are populating it but you are somehow using other instance of it. This has a higher chance of happening if you are sending data between forms as well.