主题：请教这个引用问题

此主题相关图片如下：未命名.jpg

combox2的代码是

Dim cmb2 As WinForm.ComboBox = e.Sender
Dim str As String = e.Form.Controls("ComboBox1").Value
Dim cmd2 As New SQLCommand
Dim dt2 As DataTable
cmd2.C
cmd2.CommandText = "SELECT DISTINCT 统计年月 From {table_6} where 统计年 = '" & str & "'"
dt2 = cmd2.ExecuteReader()
For Each dr2 As DataRow In dt2.Datarows
    cmb2.Items.Add(dr2("统计年月"))
Next
cmb2.SelectedIndex = 0

 

combox3的值和combox2是一样的范围，该如何引用过来呢

也就是说combox2取出来的是01 02 ，combox3的范围也是 01 02

此主题相关图片如下：未命名1.jpg

点下combox3后，combox2会增加1个怎么回事