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AutoPostBack =“ true”不适用于带有数据源的DropDownList

[英]AutoPostBack=“true” doesn't work for DropDownList with DataSource

我有以下* .aspx页面

<%@ Page Language="C#" AutoEventWireup="true"  CodeFile="Test.aspx.cs" Inherits="Admin_Test" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
<title>Untitled Page</title>
</head>
<body>
<form id="form2" runat="server">
<div>
    <asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True" DataTextField="Name" DataValueField="FieldKey" />

    <asp:Label ID="Label1" runat="server" Text="Label"></asp:Label>

</div>
</form>
</body>
</html>

和* .aspx.cs页面

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Collections.Generic;
using System.Linq;

public partial class Admin_Test : System.Web.UI.Page 
{
protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        DataClassesDataContext datacontext = new DataClassesDataContext();
        DropDownList1.DataSource = datacontext.GetAllDepartments(false);
        DropDownList1.DataBind();
    }


}
}

当我在浏览器中的dropdownList中更改值时,它会执行PostBack,但是会选择PostBack之后列表的第一项-它不会保存我的值。

GetAllDepartments(isDeleted)是一个存储过程,它返回具有两个属性(FieldKey和Name)的对象列表。

您可以这样设置事件:

protected void Page_Load(object sender, EventArgs e)
{
    DropDownList1.SelectedIndexChanged += new System.EventHandler(this.On_SelectedIndexChanged);

    if (!IsPostBack)
    {
        DataClassesDataContext datacontext = new DataClassesDataContext();
        DropDownList1.DataSource = datacontext.GetAllDepartments(false);
        DropDownList1.DataBind();
    }


}

在我看来,ViewState出了点问题。 您是否以某种方式禁用了ViewState?

我找到了一个答案-* .dbml已过时,GetAllDepartments的每个FieldKey都返回0-因此,存在项的重复值。

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