Private Sub ComboBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ComboBox1.SelectedIndexChanged
Dim conn As String
conn = "provider=microsoft.ace.oledb.12.0;data source=D:\LIANXI\Database1.mdb;Persist Security Info=False"
Dim myconn As New OleDb.OleDbConnection(conn)
Dim myselectquery As String = "select *from yuanzhu "
myconn.Open()
Dim cmd As New OleDb.OleDbCommand(myselectquery, myconn)
Dim myreader As OleDb.OleDbDataReader = cmd.ExecuteReader
myreader.Read()
ComboBox1.Items.Add(myreader(0))
myconn.Close()
End Sub

conn = "provider=microsoft.ace.oledb.12.0;data source=D:\LIANXI\Database1.mdb"
dim cn as oledbconnection
cn=new oledbconnection(conn)
dim sql as string="select * from yuanzhu"
dim da as oledbdataadapter
dim ds as new dataset
da=new oledbdataadapter(sql,cn)
da.fill(ds,"yuanzhu")
for i=0 to ds.tables(0).rows.count-1
combobox1.items.add(ds.tables(0).rows(i)("列标题"))
next
试试看，手打不确定有无问题。哈哈

不在编辑器里面vb的代码看起来好麻烦啊

mdb对应jet引擎，accdb对应ace引擎，你应该百度下连接字符串