VB.Net how to prevent listbox firing selectedindexchanged selectedvaluechanged on load - vb.net

Question

Help, When I set datasource to listbox it fires selectedindexchanged and selectedvaluechanged. How can I prevent this because this resets my value to the first item all the time
Dim SQLString As String
Dim dt As New DataTable
Dim Properties As New Properties
SQLString = "select v.attributevalue,v.value"
SQLString += " from Table "
SQLString += " Where v.attributename ='new_vehicle'"
SQLString += " order by v.value"
getDataBySQL(SQLString, dt)
lstCategory.ValueMember = "attributevalue"
lstCategory.DisplayMember = "value"
lstCategory.DataSource = dt
Dim i As Integer = ReadDataFromDatabase
If i <> 0 Then
lstCategory.SelectedValue = i
End If
Private Sub lstCategory_SelectedIndexChanged(sender As Object, e As EventArgs) Handles lstCategory.SelectedIndexChanged
End Sub
Private Sub lstCategory_SelectedValueChanged(sender As Object, e As EventArgs) Handles lstCategory.SelectedValueChanged
SetDataToDatabase(lstCategory.SelectedValue.ToString)
End Sub
also when I set valuemember to the listbox it fires selectedvaluechanged.
Essentially I want to read the database value so when I have the listbox loaded it switch the selected value to what is the value in the database
Variable i is the selectedValue I want.

Answer 1

Typically when I develop an application, I will create a Boolean variable called IsLoading and set it to false by default. I will flag this as true before any code that may be loading data and mark it as false when completed. In most cases this is in my Page Load.
Private Sub Form_Main_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
IsLoading = True
'Code to load my data goes here
IsLoading = False
End Sub
I will then add it to my dropdowns like so:
Private Sub lstCategory_SelectedValueChanged(sender As Object, e As EventArgs) Handles lstCategory.SelectedValueChanged
If Not IsLoading Then
SetDataToDatabase(lstCategory.SelectedValue.ToString)
End If
End Sub
So anything the IsLoading flag is false, the code will be allowed to run.
Hope this helps.