How do I loop through a DataGridView where RowCount / Rows.Count changes - vb.net

Question

I have a VB.Net Form with a DataGridView where I wish to change between a Detailed View and a General View.
The DataGridView shows the Distance and Estimated Time between places - called the Route Leg Data and is termed the General View
I have implemented a CheckBox to select between the general and detailed view. When the CheckBox is Checked, I am trying to loop through all of the Route Leg entries and insert the Route Steps which is the Detailed information about the Leg entries.
I have tried various loop options: For..Next, For Each...Next, While...End While, and only the first row (Route Leg) gets processed, even if I have 5 more Route Leg entries.
Important: Keep in mind that when the Detail View is selected, the DataGridView row count increments for every new Route Step entry that gets inserted.
I tried to use both dgv.RowCount and dgv.Rows.Count but I keep getting the same result.
I have added some code to show what I am trying to achieve. Any help or guidance will be much appreciated.
'Show / Hide Route Step Data
Private Sub chkShowRouteStep_CheckedChanged(sender As Object, e As EventArgs) Handles chkShowRouteStep.CheckedChanged
Try
If chkShowRouteStep.Checked Then
'Show Route Steps
For i As Integer = 0 To dgvQuote.RowCount - 1
txtRowCount.Text = i
If dgvQuote.Rows(i).Cells(0).Value.ToString <> "" Then
For j As Integer = 1 To 5
i += 1
dgvQuote.Rows.Insert(i, "Step")
'dgvQuote.Rows.Insert(j + i, "Step")
Next
End If
Next
Else
'Hide Route Steps - WORKS GREAT
For i As Integer = dgvQuote.RowCount - 1 To 0 Step -1
If dgvQuote.Rows(i).Cells(0).Value.ToString = "Step" Then
dgvQuote.Rows.RemoveAt(i)
End If
Next
End If
Catch ex As Exception
MsgBox(ex.Message)
End Try
End Sub

Answer 1

My impatience, as well as a refocus, provided me with the answer.
My focus was always on the DataGridView and the feedback from it with regards to the number of rows contained in the control.
However, the execution of a loop took a snapshot of the number of rows at the start of the loop execution and did NOT update the number of rows every time rows were added to the DataGridView.
I took a different approach where I compared my current loop number (i += 1) with the current number of rows in the DataGridView (dgv.Rows.Count - 1) thereby forcing a recheck on the number of rows. This means that any new rows added to the DataGridView will now be counted in.
I added a trigger (True/False) to be set to true if the last row in the DataGridView was reach and the While...End While loop was exited.
'Show / Hide Route Step Data
Private Sub chkShowRouteStep_CheckedChanged(sender As Object, e As EventArgs) Handles chkShowRouteStep.CheckedChanged
Try
Dim lastRow As Boolean = False 'This will get set when we have reached the last row in the DGV
Dim i As Integer = 0
If chkShowRouteStep.Checked Then
'Show Route Steps
While lastRow <> True
txtRowCount.Text = i
If dgvQuote.Rows(i).Cells(0).Value.ToString <> "" Then
For j As Integer = 1 To 2
'i += 1
dgvQuote.Rows.Insert(i + j, "", "Step")
Next
End If
'Check to see if we have reached the last row, set lastRow to TRUE if it is the last row
If i = dgvQuote.Rows.Count - 1 Then
lastRow = True
End If
i += 1
End While
Else
'Hide Route Steps - WORKS GREAT
For x As Integer = dgvQuote.RowCount - 1 To 0 Step -1
If dgvQuote.Rows(x).Cells(1).Value.ToString = "Step" Then
dgvQuote.Rows.RemoveAt(x)
End If
Next
End If
Catch ex As Exception
MsgBox(ex.Message)
End Try
End Sub
The result is as follows and error free:
Before
After

Answer 2

Since the comment in the code says you want to hide route steps, why not do just that? Instead of removing and inserting rows, populate the grid with everything and then use the checkbox to set the rows .Visible property?