How to check if Variable value is increaseing vb.net? - vb.net

Question

Hi I have listview and lable ,the lable is showing how many items in the listview
I want if the lable is increased will show msgbox
* may be it will increased alot such as 100 or 1 whatever
* It will execute the command just one if the value is increased
* it must be execute the msgbox any time if the value is increased
I'm sorry for my bad language
thank you
the code :
Private Sub Timer1_Tick(sender As Object, e As EventArgs) Handles Timer1.Tick
Dim b As String = New WebClient().DownloadString(TextBox2.Text + "/Getinfo.php")
Dim mc As MatchCollection = Regex.Matches(b, "(\w+):")
For Each x As Match In mc
Dim infoName As String = x.Groups(1).Value
Try
Dim download As String = New WebClient().DownloadString(TextBox2.Text + "/sender/info/" & infoName & "/info.txt")
Dim f As String() = download.Split(":")
Dim ls As New ListViewItem
ls.Text = infoName
For Each _x As String In f
ls.SubItems.Add(_x)
Next
Dim hTable As Hashtable = New Hashtable()
Dim duplicateList As ArrayList = New ArrayList()
Dim itm As ListViewItem
For Each itm In ListView1.Items
If hTable.ContainsKey(itm.Text) Then 'duplicate
duplicateList.Add(itm)
Else
hTable.Add(itm.Text, String.Empty)
End If
Next
'remove duplicates
For Each itm In duplicateList
itm.Remove()
Next
ListView1.Items.Add(ls)
'here I want to excute the command if the value is increased but it's timer and the code will be execute every time
Catch
End Try
Next
End Sub

Answer 1

At the top of your function do
Dim oldlength = ListView1.Items.Count
At the bottom do
If oldlength < ListView1.Items.Count Then
'here I want to excute the command if the value is increased
End If
I'm pretty sure that your MessageBox isn't really what you want but a debugging example because you think if you can get the MessageBox at the right time you've solved one of your problems (which is true).