C# 如何在选择某个值后从下拉列表中清除该值

C# 如何在选择某个值后从下拉列表中清除该值,c#,asp.net,asp.net-mvc-3,asp.net-mvc-3-areas,C#,Asp.net,Asp.net Mvc 3,Asp.net Mvc 3 Areas,大家好,我想要一种方式,当用户从下拉列表中选择一个值并输入界面上的值时,下拉列表中的值被清除,并且不再能够被选择 这是我的模型: namespace Game.Models { using System; using System.Collections.Generic; public partial class tblReview { public int ReviewID { get; set; } public string

大家好,我想要一种方式,当用户从下拉列表中选择一个值并输入界面上的值时,下拉列表中的值被清除,并且不再能够被选择

这是我的模型:

namespace Game.Models
{
    using System;
    using System.Collections.Generic;

    public partial class tblReview
    {
        public int ReviewID { get; set; }
        public string Recomendation { get; set; }
        public string AvoidOrBuy { get; set; }
        public string Score { get; set; }
        public int GameIDFK { get; set; }
        public string UserName { get; set; }

        public virtual tblGame tblGame { get; set; }
    }
}
这是我的控制器:

using System;
using System.Collections.Generic;
using System.Data;
using System.Data.Entity;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using Game.Models;

namespace Game.Controllers
{ 
    public class ReviewController : Controller
    {
        private gamezoneDBEntities db = new gamezoneDBEntities();

        //
        // GET: /Review/

        public ViewResult Index()
        {
            var Info = db.tblReviews.Include(x => x.tblGame).Where(UserInfo => UserInfo.UserName.Equals(User.Identity.Name)).ToList();
            return View(Info); 
        }

        //
        // GET: /Review/Details/5

        public ViewResult Details(int id)
        {
            tblReview tblreview = db.tblReviews.Find(id);
            return View(tblreview);
        }

        //
        // GET: /Review/Create

        public ActionResult Create()
        {
            var userGames = db.tblGames.Where(g => g.UserName == User.Identity.Name);
            ViewBag.GameIDFK = new SelectList(userGames, "GameID", "GameName");
            return View(new tblReview { UserName = @User.Identity.Name });

        } 

        //
        // POST: /Review/Create

        [HttpPost]
        public ActionResult Create(tblReview tblreview)
        {
            if (ModelState.IsValid)
            {
                db.tblReviews.Add(tblreview);
                db.SaveChanges();
                return RedirectToAction("Index");  
            }

            var userGames = db.tblGames.Where(g => g.UserName == User.Identity.Name);
            ViewBag.GameIDFK = new SelectList(userGames, "GameID", "GameName");
            return View(new tblReview { UserName = @User.Identity.Name });
        }

        //
        // GET: /Review/Edit/5

        public ActionResult Edit(int id)
        {
            tblReview tblreview = db.tblReviews.Find(id);
            ViewBag.GameIDFK = new SelectList(db.tblGames, "GameID", "GameName", tblreview.GameIDFK);
            return View(tblreview);
        }

        //
        // POST: /Review/Edit/5

        [HttpPost]
        public ActionResult Edit(tblReview tblreview)
        {
            if (ModelState.IsValid)
            {
                db.Entry(tblreview).State = EntityState.Modified;
                db.SaveChanges();
                return RedirectToAction("Index");
            }
            ViewBag.GameIDFK = new SelectList(db.tblGames, "GameID", "GameName", tblreview.GameIDFK);
            return View(tblreview);
        }

        //
        // GET: /Review/Delete/5

        public ActionResult Delete(int id)
        {
            tblReview tblreview = db.tblReviews.Find(id);
            return View(tblreview);
        }

        //
        // POST: /Review/Delete/5

        [HttpPost, ActionName("Delete")]
        public ActionResult DeleteConfirmed(int id)
        {            
            tblReview tblreview = db.tblReviews.Find(id);
            db.tblReviews.Remove(tblreview);
            db.SaveChanges();
            return RedirectToAction("Index");
        }

        protected override void Dispose(bool disposing)
        {
            db.Dispose();
            base.Dispose(disposing);
        }
    }
}
以下是观点:

@model Game.tblReview

@{
    ViewBag.Title = "Create";
}

<h2>Create</h2>

<script src="@Url.Content("~/Scripts/jquery.validate.min.js")" type="text/javascript"></script>
<script src="@Url.Content("~/Scripts/jquery.validate.unobtrusive.min.js")" type="text/javascript"></script>

@using (Html.BeginForm()) {
    @Html.ValidationSummary(true)
    <fieldset>
        <legend>tblReview</legend>

        <div class="editor-label">
            @Html.LabelFor(model => model.ReviewID)
        </div>
        <div class="editor-field">
            @Html.EditorFor(model => model.ReviewID)
            @Html.ValidationMessageFor(model => model.ReviewID)
        </div>

        <div class="editor-label">
            @Html.LabelFor(model => model.Recomendation)
        </div>
        <div class="editor-field">
            @Html.EditorFor(model => model.Recomendation)
            @Html.ValidationMessageFor(model => model.Recomendation)
        </div>

        <div class="editor-label">
            @Html.LabelFor(model => model.AvoidOrBuy)
        </div>
        <div class="editor-field">
            @Html.EditorFor(model => model.AvoidOrBuy)
            @Html.ValidationMessageFor(model => model.AvoidOrBuy)
        </div>

        <div class="editor-label">
            @Html.LabelFor(model => model.Score)
        </div>
        <div class="editor-field">
            @Html.EditorFor(model => model.Score)
            @Html.ValidationMessageFor(model => model.Score)
        </div>

        <div class="editor-label">
            @Html.LabelFor(model => model.GameIDFK, "tblGame")
        </div>
        <div class="editor-field">
            @Html.DropDownList("GameIDFK", String.Empty)
            @Html.ValidationMessageFor(model => model.GameIDFK)

        </div>

        <div class="editor-label">
            @Html.LabelFor(model => model.UserName)
        </div>
        <div class="editor-field">
            @Html.EditorFor(model => model.UserName)
            @Html.ValidationMessageFor(model => model.UserName)
        </div>

        <p>
            <input type="submit" value="Create" />
        </p>
    </fieldset>
}

<div>
    @Html.ActionLink("Back to List", "Index")
</div>
@model Game.tblReview
@{
ViewBag.Title=“创建”;
}
创造
@使用(Html.BeginForm()){
@Html.ValidationSummary(true)
tblReview
@LabelFor(model=>model.ReviewID)
@EditorFor(model=>model.ReviewID)
@Html.ValidationMessageFor(model=>model.ReviewID)
@LabelFor(model=>model.recondation)
@EditorFor(model=>model.recondation)
@Html.ValidationMessageFor(model=>model.recondation)
@LabelFor(model=>model.AvoidOrBuy)
@EditorFor(model=>model.AvoidOrBuy)
@Html.ValidationMessageFor(model=>model.AvoidOrBuy)
@LabelFor(model=>model.Score)
@EditorFor(model=>model.Score)
@Html.ValidationMessageFor(model=>model.Score)
@Html.LabelFor(model=>model.GameIDFK,“tblGame”)
@Html.DropDownList(“GameIDFK”,String.Empty)
@Html.ValidationMessageFor(model=>model.GameIDFK)
@LabelFor(model=>model.UserName)
@EditorFor(model=>model.UserName)
@Html.ValidationMessageFor(model=>model.UserName)

} @ActionLink(“返回列表”、“索引”)
我们将非常感谢你的帮助


如果需要什么,请询问。

这可能不是最好的方法,但我会尝试一下。我不明白您为什么要重定向到//返回重定向操作(“索引”);然后返回一个视图???/您也可以从tblreview获得一个id,而不需要表单集合

 <div class="editor-field">
                @Html.DropDownList("GameIDFK", String.Empty)
                @Html.ValidationMessageFor(model => ViewBag.GameIDFK)
            </div>


    [HttpPost]
    public ActionResult Create(tblReview tblreview, FormCollection formCollection)
       {
                if (ModelState.IsValid)
                {

                    db.tblReviews.Add(tblreview);
                    db.SaveChanges();
                   // return RedirectToAction("Index");  
                }
                 int gameid=Convert.ToInt32(formCollection["GameIDFK"]);
                var userGames = (from g in db.tblGames where g.UserName== User.Identity.Name && g.GameID!=gameid select g).ToList();
                ViewBag.GameIDFK = new SelectList(userGames, "GameID", "GameName");
                return View(new tblReview { UserName = @User.Identity.Name });
    }

@Html.DropDownList(“GameIDFK”,String.Empty)
@Html.ValidationMessageFor(model=>ViewBag.GameIDFK)
[HttpPost]
公共操作结果创建(tblReview tblReview、FormCollection FormCollection)
{
if(ModelState.IsValid)
{
db.tblReviews.Add(tblreview);
db.SaveChanges();
//返回操作(“索引”);
}
int gameid=Convert.ToInt32(formCollection[“GameIDFK]”);
var userGames=(从db.tblGames中的g开始,其中g.UserName==User.Identity.Name&&g.GameID!=GameID选择g);
ViewBag.GameIDFK=新的选择列表(userGames、“GameID”、“GameName”);
返回视图(新的tblReview{UserName=@User.Identity.Name});
}

我对你的问题有点困惑。因此,用户可以看到一个表单。他们点击下拉菜单,然后从下拉菜单中选择“魔兽争霸2”。现在你想立即从列表中删除魔兽争霸II吗?是的,从下拉列表中删除,而不是数据库。当他们提交时,你说的是正确的,它重定向回同一视图,或者当他们只选择一次更改时,我要它,所以当他们提交值时,它被重定向到同一页面,以便他们可以选择另一个游戏,等等,但是已选择allready的值不应显示在列表中。它删除一个值,然后当我选择另一个值时,前一个值返回。我希望这样,当用户选择一个游戏,即gta,然后按submit键时,该值将消失,而不会像我的帖子所说的那样再次被选择。同样,当我注销时,该值将返回。我想要一种方式,用户选择一个游戏,在界面上输入所有值,然后提交下拉列表中的值,这样就不能再选择了。因此,一旦输入了评论,游戏就不能再被选择了。谢谢,答案非常接近我想要的。谢谢,我理解你,对数据库设计更清楚。在这种情况下,我可以建议创建一个临时表,以便此表将包含他选择的所有用户id和游戏,以及当你创建另一个临时表时下拉列表您将检查游戏是否在临时表中,您将从下拉列表中将其删除