保留回发后动态绑定的DropDownList的选定值

本文介绍了保留回发后动态绑定的DropDownList的选定值的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我有我的ASPX标记声明，像这样一个DropDownList：

I have a dropdownlist which I declare on the aspx markup like so:

<asp:DropDownList ID="State" runat="server"></asp:DropDownList>

然后我将它绑定在页加载像这样：

Then I bind it on page load like so :

protected void Page_Load(object sender, EventArgs e) { BindDropdowns(); } private void BindDropdowns() { State.DataSource = DataAccess.GetStates(); State.DataValueField = "FieldId"; State.DataTextField = "FieldName"; State.DataBind(); }

选择的值不回发后保留下来，我也可以不火的selectedindexchangedevent。怎么了？

The selected value is not retained after postback, I also cannot fire the selectedindexchangedevent. What's wrong ?

推荐答案

请改变你的code是这样的：

please change your code like this:

protected void Page_Load(object sender, EventArgs e) { if (!Page.IsPostback) BindDropdowns(); }

这意味着，在第一次页面加载你的下拉控件只能被绑定一次，

This means that your dropdown control is only bound once on first pageload