PerformCallback(珍藏版)

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

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
     <script language="javascript" type="text/javascript">

         //客户端处理下拉框选择项改变事件,client端aspxcombox下拉框改变事件为SelectedIndexChanged

         function OnEmployeesChanged(s) {
                //PerformCallback事件实际上时dev系列控件客户端服务器端异步通信的"大使",通过PerfromCallback事件
                //将客户端的通信要求传递给服务端,在服务端通过控件的callback事件来接受相关参数并进行页面异步刷新
             //向服务器发送数据
             alert("向服务发送:" + s.GetValue());
                devcbxChi.PerformCallback(s.GetValue());

         } 

    </script> 
    <style type="text/css">
        .style1
        {
             100%;
        }
        .style2
        {
             231px;
        }
    </style>
</head>
<body>
    <form id="form1" runat="server">
    <div>

        <table class="style1">
            <tr>
                <td class="style2">
                    主动向服务器发起挑战</td>
                <td>

    <dx:ASPxComboBox runat="server" ID="devcbxPar2" 
        EnableSynchronization="False" ClientInstanceName="devcbxPar2" Width="160px" 
                        IncrementalFilteringMode="StartsWith"> 
        <ClientSideEvents SelectedIndexChanged="function(s, e) { OnEmployeesChanged(s); }"></ClientSideEvents> 
        <Items>
            <dx:ListEditItem Text="数据0" Value="0" />
            <dx:ListEditItem Text="数据1" Value="1" />
            <dx:ListEditItem Text="数据2" Value="2" />
            <dx:ListEditItem Text="数据3" Value="3" />
        </Items>
    </dx:ASPxComboBox> 

                </td>
            </tr>
            <tr>
                <td class="style2">
                    向服务器发起挑战</td>
                <td>

    <dx:ASPxComboBox runat="server" ID="devcbxChi" DropDownStyle="DropDownList" EnableIncrementalFiltering="True"
        EnableSynchronization="False" ClientInstanceName="devcbxChi"  Width="160px" oncallback="devcbxChi_Callback"> 
    </dx:ASPxComboBox>   

                </td>
            </tr>
        </table>

        <br />

    </div> 
    </form>
</body>
</html>
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

public partial class PerformCallback : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }

    //服务器接收挑战
    protected void devcbxChi_Callback(object sender, DevExpress.Web.CallbackEventArgsBase e)
    {
        devcbxChi.Items.Add("这是来自客户端的数据:"+e.Parameter);

        devcbxChi.SelectedIndex = devcbxChi.Items.Count - 1;


    }
}
原文地址:https://www.cnblogs.com/qqhfeng/p/10283503.html