Find the last row in a datset?

[Rocky48]

I have a textbox which the user types the ID number of the record to update that record. I found when I inadvertantly typed a number greater than the last ID number the computer hung, because there whas no such record.

Therefore I want to check the last row number so that I can cause a message to be displayed if that number is exceeded.

Here is the code:

Imports System.Data.SqlClient
Public Class FrmOne
Private MyDatAdp As New SqlDataAdapter
Private MyDataTbl As New DataTable
Private MyRowPosition As Integer = 0
Private Sub Findbtn_Click(sender As Object, e As EventArgs) Handles Findbtn.Click
Dim VNo As String = VNotxt.Text
Dim VID As String = VNotxt.Text
Dim cn As New SqlConnection With {.ConnectionString = "Data Source=DESKTOP-S7FRNAL\SQLEXPRESS;Initial Catalog=Verses_Find;Integrated Security=True"}
Dim MyDatAdp As New SqlDataAdapter("Select VID, VERSE from Verse where VID = @VID", cn)
MyDatAdp.SelectCommand.Parameters.AddWithValue("@VID", VNo)
Dim MyDataTbl As New DataTable
MyDatAdp.Fill(MyDataTbl)

If String.IsNullOrEmpty(VNotxt.Text) Then
MsgBox("You did not enter a number")

Else
Dim MyDataRow As DataRow = MyDataTbl.Rows(0)
Dim strVerse As String = MyDataRow("Verse").ToString
Versetxt.Text = strVerse
End If

End Sub

Private Sub btnClear_Click(sender As Object, e As EventArgs) Handles btnClear.Click
VNotxt.Text = ""
Versetxt.Text = ""
End Sub
Private Sub BtnSave_Click(sender As Object, e As EventArgs) Handles btnSave.Click

Using cn As New SqlConnection With {.ConnectionString = "Data Source=DESKTOP-S7FRNAL\SQLEXPRESS;Initial Catalog=Verses_Find;Integrated Security=True"},
cmd As New SqlCommand

cn.Open()
cmd.Connection = cn
cmd.CommandText = "Update Verse Set [Verse] = @Verse Where VID = @VID"
cmd.Parameters.AddWithValue("@VID", Me.VNotxt.Text)
cmd.Parameters.AddWithValue("@Verse", Me.Versetxt.Text)

Dim num = cmd.ExecuteNonQuery
MessageBox.Show("Number of Records Updated = " & num.ToString)
End Using

End Sub

Private Sub btnShowSecond_Click_1(sender As Object, e As EventArgs)
Dim SecondForm As New frmSecond
SecondForm.Show()
End Sub

Private Sub btnClose_Click(sender As Object, e As EventArgs) Handles btnClose.Click
Close()
End Sub

Private Sub FrmOne_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Me.TopMost = True
Me.WindowState = FormWindowState.Maximized
End Sub
End Class

I was going to put an EsleIf expression after the mesage box that tells you if you have not typed a number.

The knowledge is limited so not sure how to do this?

Your help will be appreciated!



TEH

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