[Genius Live]

This code will do the job
The code for this collection of values ​​in a ListBox1 and put it in the TextBox4

كود :

Dim x As Double = 0
        For i As Integer = 0 To ListBox1.Items.Count - 1
            ListBox1.SelectedIndex = i
            x += ListBox1.SelectedItem.ToString
        Next
        TextBox4.Text = x

Use the same code to collect the other List Box

my greetings