Public Class Form1
    Private mFirmen As New List(Of Firma)
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles MyBase.Load
        mFirmen.Add(New Firma("Firma1", 10, 10))
        mFirmen.Add(New Firma("Firma2", 20, 30))
        mFirmen.Add(New Firma("Firma3", 30, 0))
        mFirmen.Add(New Firma("Firma4", 40, 10))
        mFirmen.Add(New Firma("Firma5", -10, 10))
    End Sub
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button1.Click
        Dim referenzFirma As Firma = New Firma("ReferenzFirma", 0, 0)
        Dim firmenInNaehe = From f As Firma In mFirmen Where Entfernung( _
          referenzFirma, f) <= 25 Select f
        Dim dt As DataTable = FirmenToDataTable(referenzFirma, firmenInNaehe)
        DataGridView1.DataSource = dt
    End Sub
 
    Public Function FirmenToDataTable(ByVal referenzFirma As Firma, ByVal _
      firmen As IEnumerable(Of Firma)) As DataTable
        Dim dt As New DataTable
        dt.Columns.Add("Name", GetType(String))
        dt.Columns.Add("Entfernung", GetType(Double))
        dt.Columns.Add("X", GetType(Integer))
        dt.Columns.Add("Y", GetType(Integer))
        For Each f As Firma In firmen
            Dim r As DataRow = dt.NewRow
            r("Name") = f.Name
            r("Entfernung") = Entfernung(referenzFirma, f)
            r("X") = f.X
            r("Y") = f.Y
            dt.Rows.Add(r)
        Next
        Return dt
    End Function
 
    Public Function Entfernung(ByVal firmaA As Firma, ByVal firmaB As Firma) As _
      Double
        Return ((Math.Abs(firmaB.X - firmaA.X) ^ 2) + (Math.Abs(firmaB.Y - _
        firmaA.Y) ^ 2)) ^ 0.5
    End Function
 
End Class
 
Public Class Firma
    Public Name As String
    Public X As Integer
    Public Y As Integer
    Public Sub New(ByVal n As String, ByVal xValue As Integer, ByVal yValue As _
      Integer)
        Me.Name = n
        Me.X = xValue
        Me.Y = yValue
    End Sub
End Class