Option Infer On
 
Public Class frmCount
 
    Dim dt As New DataTable
    Dim dtx As DataTable
 
    Dim dgv As New DataGridView With
        {.Parent = Me, .AllowUserToAddRows = False}
 
 
    Private Sub frmCount_Load(sender As Object, _
               e As EventArgs) Handles MyBase.Load
 
        'Einige Testdaten erstellen
        With dt.Columns
            .Add("ID", GetType(Integer))
            .Add("Name", GetType(String))
            .Add("Arbeitsschritt", GetType(String))
 
        End With
 
        Dim namen() As String = _
           {"Müller E.", "Schneider K.", "Meier L.", "Üzgül E."}
        Dim schritte() As String = _
           {"Falten", "Schneiden", "Bohren", "Schleifen", "Messen"}
 
        Dim rndm As New Random(1234)
        For i As Integer = 1 To 1000
            'zufällige Datensätze
            dt.Rows.Add(i, namen(rndm.Next(0, 4)), schritte(rndm.Next(0, 5)))
        Next i
 
        'LINQ: Gruppieren/Sortieren und Zählen der Datensätze
        Dim q = From r As DataRow In dt.AsEnumerable
                Let name As String = r("Name").ToString
                Let schritt As String = r("Arbeitsschritt").ToString
                Order By name, schritt
                Group By name, schritt
                Into Anzahl = Group, Count()
 
        'Listenelemente des anonymen Typs in die Sätze einer Datatable eintragen
        dtx = dt.Clone
        dtx.Columns.Add("Anzahl")
 
        For i As Integer = 0 To q.Count - 1
            dtx.Rows.Add(i, q(i).name, q(i).schritt, q(i).Count)
        Next i
 
        'Anzeigen
        dgv.DataSource = dtx
 
    End Sub
End Class