讲讲怎么在 ASP.NET MVC2中使用用户控件。首先我们新建一个用户控件，
我们命名为SelectGroup.ascx，代码如下
<%@ Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl" %>
<script language="javascript" type="text/javascript" src="<%=Url.Content("~/Areas/Util/Scripts/SelectGroup.js") %>"></script>
<div>
<table>
<tr>
<td style="text-align:right">
招生批次
</td>
<td>
<select id="admissionBatch" style=" 150px">
</select>
</td>
<td style="text-align:right; 80px">
学历层次
</td>
<td>
<select id="edcuationLevel" style=" 150px">
</select>
</td>
<td style="text-align:right; 80px">
专业名称
</td>
<td>
<select id="professional" style=" 150px">
</select>
</td>
</tr>
</table>
</div>
我们再编写其对应的控制器如下
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
namespace EducationManage.Areas.Util.Controllers
{
using Utility.Json;
using EducationManage.Areas.Util.Models;
public class SelectGroupController : Controller
{
//
// GET: /Util/SelectGroup/
SelectgroupEntities selectgroupEntities = new SelectgroupEntities();
/// <summary>
/// 招生批次
/// 李磊 2010-10-29
/// </summary>
/// <returns></returns>
public JsonResult GetAdmissionBatch()
{
List<SG_Admission_Batchs> admissionBatchsList =selectgroupEntities.admission_batchs.ToList();
return Json(admissionBatchsList, JsonRequestBehavior.AllowGet);
}
/// <summary>
/// 学历层次
/// 李磊 2010-10-29
/// </summary>
/// <returns></returns>
public JsonResult GetEducationLevel()
{
List<SG_Education_Levels> educationLevelList = selectgroupEntities.education_levels.ToList();
return Json(educationLevelList, JsonRequestBehavior.AllowGet);
}
/// <summary>
/// 专业
/// 李磊 2010-10-29
/// </summary>
/// <returns></returns>
public JsonResult GetProfessional()
{
List<SG_Professional> professionalList = selectgroupEntities.professional.ToList();
return Json(professionalList, JsonRequestBehavior.AllowGet);
}
/// <summary>
/// 学籍批次
/// 李磊 2010-10-29
/// </summary>
/// <returns></returns>
public JsonResult GetRollBatch()
{
List<SG_Roll_Batchs> rollBatchList = selectgroupEntities.roll_batchs.ToList();
return Json(rollBatchList, JsonRequestBehavior.AllowGet);
}
/// <summary>
/// 专业学历层次联动
/// 李磊 2010-10-29
/// </summary>
/// <param name="id"></param>
/// <returns></returns>
public JsonResult GetProfessionalByEducationLevel(string id)
{
try
{
List<string> professionalIdList = selectgroupEntities.professional_educationlevel.Where(pe => pe.education_id == id).Select(pe => pe.prefessional_code).ToList();
List<SG_Professional> professionalList = selectgroupEntities.professional.Where(p => professionalIdList.Contains(p.prefessional_code)).ToList();
return Json(professionalList, JsonRequestBehavior.AllowGet);
}
catch
{
return null;
}
}
}
}
好的，我们接着编写js.
首先在js的顶层引入 ///<reference path = "../../../Scripts/jQuery-1.4.1.js"/>这样编写js代码就有智能提示，如下
$(document).ready(function () {
$.ajaxSetup({
cache: false
});
$.getJSON("/SelectGroup/GetAdmissionBatch/", function (data) {
$("#admissionBatch").append("<option value=''>请选择</option>");
$.each(data, function (i, item) {
$("<option></option>")
.val(item["admission_batch_id"])
.text(item["name"])
.appendTo($("#admissionBatch"));
});
});
$.getJSON("/SelectGroup/GetEducationLevel/", function (data) {
$("#edcuationLevel").append("<option value=''>请选择</option>");
$.each(data, function (i, item) {
$("<option></option>")
.val(item["education_id"])
.text(item["name"])
.appendTo($("#edcuationLevel"));
});
});
$.getJSON("/SelectGroup/GetProfessional/", function (data) {
$("#professional").append("<option value=''>请选择</option>");
$.each(data, function (i, item) {
$("<option></option>")
.val(item["prefessional_code"])
.text(item["name"])
.appendTo($("#professional"));
});
});
$("#edcuationLevel").change(function () {
$("#professional").empty();
$("#professional").append("<option value='0'>请选择</option>");
$.getJSON("/SelectGroup/GetProfessionalByEducationLevel/" + $("#edcuationLevel").val(), function (data) {
$.each(data, function (i, item) {
$("<option></option>")
.val(item["prefessional_code"])
.text(item["name"])
.appendTo($("#professional"));
});
});
});
})
ok，好了，我们看看在页面怎么引用
<%Html.RenderPartial("~/Areas/Util/Views/Shared/SelectGroup.ascx"); %>
只要你将这段代码放在页面上即可。Html.RenderPartial有很多重载，你也可以给用户控件传递一个需要绑定的对象。说到这里谈谈Html.RenderPartial和Html.Partial的区别。Html.RenderPartial是直接输出至当前HttpContext，而Html.Partial是将视图内容直接生成一个字符串并返回。所以在引用的时候不一样分别为<% Html.RenderPartial("~/Areas/Util/Views/Shared/SelectGroup.ascx"); %>和<%=Html.Partial("~/Areas/Util/Views/Shared/SelectGroup.ascx"); %>。说到这两个不免要说Html.RenderAction，它是通过Controller中的Action来调用用户控件。上面的代码大家可以根据js和控制器代码看到，每个下拉列表的绑定都有自己的控制器返回数据，在页面加载完成的时候去调用自己的控制器获取下拉列表数据。如果我们用Html.RenderAction就没有那么麻烦了，看看控制器代码
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
namespace EducationManage.Areas.Util.Controllers
{
using Utility.Json;
using EducationManage.Areas.Util.Models;
public class SectionGroupController : Controller
{
//
// GET: /Util/SectionGroup/
SelectgroupEntities selectgroupEntities = new SelectgroupEntities();
public ActionResult Index()
{
List<SG_Admission_Batchs> admissionBatchList = selectgroupEntities.admission_batchs.ToList();
SelectList admissionBatch = new SelectList(admissionBatchList, "admission_batch_id", "name", "");
ViewData.Add("admissionBatch", admissionBatch);
List<SG_Education_Levels> educationLevelList = selectgroupEntities.education_levels.ToList();
SelectList educationLevel = new SelectList(educationLevelList, "education_id", "name", "");
ViewData.Add("educationLevel", educationLevel);
List<SG_Professional> professionalList = selectgroupEntities.professional.ToList();
SelectList professional = new SelectList(professionalList, "prefessional_code", "name", "");
ViewData.Add("professional", professional);
return PartialView("~/Areas/Util/Views/Shared/SectionGroup.ascx");
}
}
}
再看看前台
<%@ Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl" %>
<script language="javascript" type="text/javascript" src="<%=Url.Content("~/Areas/Util/Scripts/SelectGroup.js") %>" />
<div>
<table>
<tr>
<td style="text-align: right">
招生批次
</td>
<td>
<%:Html.DropDownList("admissionBatch", ViewData["admissionBatch"] as SelectList, "请选择", new { id = "admissionBatch", style = " 150px" })%>
</td>
<td style="text-align: right; 80px">
学历层次
</td>
<td>
<%:Html.DropDownList("edcuationLevel", ViewData["educationLevel"] as SelectList, "请选择", new { id = "edcuationLevel", style = " 150px" })%>
</td>
<td style="text-align: right; 80px">
专业名称
</td>
<td>
<%:Html.DropDownList("professional", ViewData["professional"] as SelectList, "请选择", new { id = "professional", style = " 150px" })%>
</td>
</tr>
</table>
</div>
在这里我们一次性就获取到了所有下拉列表要绑定的数据。我们只需要在前台这样应用即可<%Html.RenderAction("Index", "SectionGroup");%>。好了，在MVC2中使用用户控件就是这么简单。
本文出自 “微软技术” 博客，请务必保留此出处http://leelei.blog.51cto.com/856755/412702