asp.net-mvc - 在 mvc 中提交表单后保存下拉列表状态

Question

我有一个表单和 Html.DropDownList 。表单提交后，下拉列表状态更改为默认值。表单提交后如何保持下拉列表状态？

@using (Html.BeginForm("Result", "Controller", FormMethod.Post, new { id = "Form" }))
           {
             @Html.DropDownListFor(x => x.DropList, new[] { 
                new SelectListItem() {Text = "first", Value = "first"}, 
                new SelectListItem() {Text = "second", Value = "second"},
                new SelectListItem() {Text = "third", Value = "third"} 
                }, "DefaultState")

提前致谢。

Answer 1

使用 SelectListItem 的 Selected 属性

此外，请确保 Model.DropList 的值是从帖子中在您的控制器中设置的。

  @using (Html.BeginForm("List", "Home", FormMethod.Post, new { id = "Form" }))
       {
         @Html.DropDownListFor(x => x.DropList, new[] { 
            new SelectListItem() {Text = "first", Value = "first", Selected = Model.DropList == "first"}, 
            new SelectListItem() {Text = "second", Value = "second", Selected = Model.DropList == "second"},
            new SelectListItem() {Text = "third", Value = "third", Selected = Model.DropList == "third"} 
            }, "DefaultState")

Answer 2

你不能。除非在提交之后，您将模型传回视图。你为什么要这样做？因为在表单提交之后，表单应该重置并为另一个数据输入会话做好准备，不是吗？