如何使用MVC驗證帶有客戶端驗證的dropdownlist元素？

Question

我想為下拉列表實現客戶端驗證。

Model 

public partial class Beach
    {
        public int Beach_ID{ get; set; }
        [Required]
        public string NAME { get; set; }

        [Required]
        public Nullable<int> LOCATION_ID { get; set; }


        public virtual LOCATION LOCATION { get; set; }
    }

Controller

 public ActionResult Edit(int? id)
        {

            if (id == null)
            {
                return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
            }
            BEACH BEACH  = db.BEACH .Find(id);
            if (BEACH  == null)
            {
                return HttpNotFound();
            }
             ViewBag.LOCATION = new SelectList(db.LOCATION, "LOCATION_ID", "LOCATION_NAME", BEACH.LOCATION_ID);
            return View(BEACH);
        }

View

 <div class="form-group">
            <div class="col-md-10">
                @Html.DropDownList("LOCATION", null, "Select Location", htmlAttributes: new { @class = "form-control" })
                @Html.ValidationMessageFor(model => model.LOCATION_ID, "", new { @class = "text-danger" })
            </div>
        </div>

名稱字段是必填字段，如果表單提交為空白，則客戶端驗證工作正常。 但是，下拉列表僅適用於服務器端驗證。

Answer 1

你可以使用JQuery來驗證按鈕點擊。

您可以通過以下方式向DropDownList添加ID

  @Html.DropDownList("LOCATION", null, "Select Location", htmlAttributes: new {  @id="dropdownid",@class = "form-control" })

並在腳本標記中編寫以下代碼。

 $('#Submit').click(function(){
    var ddlvalue= $("#dropdownid option:selected").val();
    if(ddlvalue!='-1')
    {    
      //Do your work.
    }
  else
  alert('Please select Location");
   });

Answer 2

asp.net mvc jquery下拉列表驗證

你可以參考上面的鏈接，它可能有助於找出你的問題。