SelectedIndexChanged事件不火(SelectedIndexChanged even

我已经添加了AutoPostBack = "true"属性的下拉列表中。 它不工作。

<asp:DropDownList CssClass="dropDownList" ID="ddlBusinessUnit" 
                  AutoPostBack="true" runat="server" Width="250px"   
                  OnSelectedIndexChanged="ddlBusinessUnit_SelectedIndexChanged">
</asp:DropDownList>

后面的代码：

Protected Sub ddlBusinessUnit_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs)
    Response.Write("Hello")
End

我怎样才能确保该事件方法被调用？

Answer 1:

你在每一个回发填充你的下拉列表？

使用的IsPostBack检查网页是否加载首次与否。

If Not IsPostBack Then
   BinDdlBusinessUnit()
End If

文章来源: SelectedIndexChanged event doesn't fire