This is a VB.NET implementation of a bubble sort.  The array has been declared with form level scope and initialised in the form’s load event handler.

An enhanced version of the program is also shown.  In this version a Boolean flag is tested to see if there has been a swap during each pass.  If there have been no swaps, it is assumed that the data is now in order and there is no need for any more passes.

Public Class Form1

    Dim aData(9) As Integer
 
    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles Me.Load
        aData(0) = 6
        aData(1) = 5
        aData(2) = 9
        aData(3) = 10
        aData(4) = 8
        aData(5) = 7
        aData(6) = 4
        aData(7) = 3
        aData(8) = 1
        aData(9) = 2
    End Sub
 
    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        Dim iPass As Integer
        Dim iTemp As Integer
        Dim i As Integer
 
        For iPass = 1 To 9
            For i = 0 To 8
                If aData(i) > aData(i + 1) Then
                    iTemp = aData(i + 1)
                    aData(i + 1) = aData(i)
                    aData(i) = iTemp
                End If
            Next
        Next
 
        'output bubble sorted array
        Dim stOutput As String
        For i = 0 To 9
            stOutput = stOutput & aData(i) & vbNewLine
        Next
        MsgBox(stOutput)
    End Sub
 
    Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
        Dim iPass As Integer
        Dim iTemp As Integer
        Dim i As Integer
        Dim bSwap As Boolean
 
        For iPass = 1 To 9
            For i = 0 To 8
                If aData(i) > aData(i + 1) Then
                    iTemp = aData(i + 1)
                    aData(i + 1) = aData(i)
                    aData(i) = iTemp
                    bSwap = True
                End If
            Next
            If bSwap = False Then
                Exit For
            Else
                bSwap = False
            End If
        Next
 
        'output bubble sorted array
        Dim stOutput As String
        For i = 0 To 9
            stOutput = stOutput & aData(i) & vbNewLine
        Next
        MsgBox(stOutput)
    End Sub
End Class