[alfauori]

تم اجراء الحل بس يمكن في شئ افضل

 Dim MyDateTime As DateTime = Nothing

        Dim MyTimeSpan As New TimeSpan

        Dim a As Integer = 0

        Dim a1 As Integer = 0

        Dim x As Integer = 0

        For Each S As String In ListBox1.Items

            MyDateTime = DateTime.Parse(S)

            MyTimeSpan = MyTimeSpan.Add(New TimeSpan(MyDateTime.Hour, MyDateTime.Minute, 0))

            a += MyDateTime.Hour

        Next

        a1 = (a - MyDateTime.Hour) / 24

        If (MyTimeSpan.Minutes) < 10 Then

            TextBox1.Text = a1 & " / " & MyTimeSpan.Hours & ":" & "0" & MyTimeSpan.Minutes

        Else

            TextBox1.Text = a1 & " / " & MyTimeSpan.Hours & ":" & MyTimeSpan.Minutes

        End If