Public Class Form1
 
    Dim dtWochenplan As DataTable
    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
 
        dtDatenInitialisieren()
        DataGridView1Initialisieren()
 
    End Sub
 
    Private Sub dtDatenInitialisieren()
 
        dtWochenplan = New DataTable
        dtWochenplan.TableName = "Wochenplan"
 
        Dim keys(1) As DataColumn
        Dim column As New DataColumn
        column.DataType = System.Type.GetType("System.Int32")
        With column
            .ColumnName = "ID"
            .AutoIncrement = True
            .AutoIncrementStep = 1
        End With
        dtWochenplan.Columns.Add(column)
        keys(0) = column
        dtWochenplan.PrimaryKey = keys
 
        column = New DataColumn
        column.DataType = System.Type.GetType("System.String")
        column.ColumnName = "Name"
        dtWochenplan.Columns.Add(column)
 
        column = New DataColumn
        column.DataType = System.Type.GetType("System.String")
        column.ColumnName = "Tag"
        dtWochenplan.Columns.Add(column)
 
    End Sub
 
    Private Sub DataGridView1Initialisieren()
        With DataGridView1
            .DataSource = dtWochenplan
            .ReadOnly = False
            .AllowUserToAddRows = True
            .AllowUserToDeleteRows = False
            .SelectionMode = DataGridViewSelectionMode.FullRowSelect
            .MultiSelect = False
            .AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.Fill
            .ScrollBars = ScrollBars.Both
            .RowsDefaultCellStyle.BackColor = Color.White
            .AlternatingRowsDefaultCellStyle.BackColor = Color.AliceBlue
        End With
    End Sub
 
    Private Sub DataGridView1_CellMouseDown(sender As Object, e As _
      DataGridViewCellMouseEventArgs) Handles DataGridView1.CellMouseDown
        c = e.ColumnIndex
        r = e.RowIndex
    End Sub
 
    Dim r As Integer = 0
    Dim c As Integer = 0
 
    Private Sub DataGridView1_MouseClick(sender As Object, e As MouseEventArgs) _
      Handles DataGridView1.MouseClick
 
        If e.Button = MouseButtons.Left Or c <> 1 Then
            Exit Sub
        End If
 
        DataGridView1.CurrentCell = DataGridView1(c, r)
        DataGridView1.BeginEdit(True)
 
        Dim MouseLeft As Integer = MousePosition.X
        Dim MouseTop As Integer = MousePosition.Y
 
        Dim f2 As New Form2
        f2.StartPosition = FormStartPosition.Manual
        f2.Left = MouseLeft
        f2.Top = MouseTop
 
        f2.ShowDialog()
 
        Dim Rueckgabe As String = f2.Nachname
 
        DataGridView1.CurrentCell.Value = Rueckgabe
 
        DataGridView1.EndEdit(True)
 
    End Sub
 
 
End Class

Public Class Form2
 
    Public Nachname As String
    Private Sub Form2_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        With ComboBox1
            .Items.Add("Müller")
            .Items.Add("Schmidt")
            .Items.Add("Meier")
        End With
    End Sub
 
    Private Sub btnOK_Click(sender As Object, e As EventArgs) Handles _
      btnOK.Click
        Nachname = ComboBox1.Text
        Me.Close()
    End Sub
End Class

EALA FREYA FRESENA