在VB中如何用列表框查询？

数据库没有设计好
你可以用一个总类表（比如皮肤疾病、儿科疾病等）和一个子类表

Class(id,name)
SubClass(id,cid,name,Symptom)

两个ComboBox一个TextBox
Dim conn As ADODB.Connection
Private Sub Combo1_Click()
Dim rs As ADODB.Recordset
Dim strSql As String
strSql = "select subclass.name from subclass left join class on subclass.cid = class.id where class.name ='" & Combo1.Text & "'"
Set rs = OpenRecordset(strSql, conn)
Combo2.Clear
Do While Not rs.EOF
Combo2.AddItem rs!Name
rs.MoveNext
Loop
End Sub

Private Sub Combo2_Click()
Dim rs As ADODB.Recordset
Dim strSql As String
strSql = "select Symptom from subclass where name ='" & Combo2.Text & "'"
Set rs = OpenRecordset(strSql, conn)
Text1.Text = rs!Symptom
End Sub

Private Sub Form_Load()
Set conn = OpenConnForAccess(