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由SQL Access填充的Vb组合框_Sql_Vb.net_Ms Access 2007 - Fatal编程技术网

由SQL Access填充的Vb组合框

由SQL Access填充的Vb组合框,sql,vb.net,ms-access-2007,Sql,Vb.net,Ms Access 2007,大家好,我正在尝试创建一个由SQL查询填充的组合框,但是每当我单击下拉列表时,下面的代码不会显示任何结果,请帮助我。谢谢 Private Sub eNumText_SelectedIndexChanged(sender As Object, e As EventArgs) Handles eNumText.SelectedIndexChanged con.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0; Data So

大家好,我正在尝试创建一个由SQL查询填充的组合框,但是每当我单击下拉列表时,下面的代码不会显示任何结果,请帮助我。谢谢

Private Sub eNumText_SelectedIndexChanged(sender As Object, e As EventArgs) Handles eNumText.SelectedIndexChanged

        con.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0; Data Source= c:\Databse\Company_db.accdb"
        Dim cmd As New OleDbCommand
        con.Open()
        cmd.Connection = con
        cmd.CommandText = "SELECT EmpID from tbl_empinfo"

        Dim dr As OleDbDataReader = cmd.ExecuteReader

        While dr.Read
            eNumText.Items.Add(dr.Item(0))
        End While
        dr.Close()

您的代码不会被触发,因为我猜组合框中没有项目,请将代码移动到按钮单击或表单加载事件,它将工作:

Private Sub Form1_Load(sender As Object, e As System.EventArgs) Handles Me.Load
  'Your Code
   ....
End Sub

5个问题,包含大量详细帮助和0个已接受的答案…单击下拉列表不会触发此代码运行我们来这里寻求帮助,以避免垃圾言论@puropoix,有些用户与您不同,是新手,您是超级铁杆程序员垃圾言论是什么?我刚刚花了两个小时给你一个答案,你在那之前一个小时才得到答案。你已经得到了大量的帮助…但你还没有承认一个你在索引上做的改变。如果没有项目,您甚至不会触发该事件,也不会执行代码。