Question

我有一个View for Update操作，我的模型有enum属性：

public enum DeliveryStatusType
{
    Active = 1,
    Deactive = 2,
}

基本上，我填充enum并使用DropDownList。为了理解发生了什么，我将其简化并尽可能简单地发布在这里。

我已经尝试了Html.DropDownList和Html.DropDownListFor，这里是视图：

第一个示例（未在此处设置所选内容）：

@Html.DropDownListFor(model => model.DeliveryStatus, new SelectListItem[] {
        new SelectListItem { 
            Selected = false, 
            Text = "Active Delivery", 
            Value = "1" },
        new SelectListItem { 
            Selected = true, 
            Text = "Deactive Delivery", 
            Value = "2" }}) //Notice that I manually set the 2nd true

第二个例子（未在此处设置选择）：

@Html.DropDownList("DeliveryStatus", new SelectListItem[] {
        new SelectListItem { 
            Selected = false, 
            Text = "Active Delivery", 
            Value = "1" },
        new SelectListItem { 
            Selected = true, 
            Text = "Deactive Delivery", 
            Value = "2" }}) //Notice that I manually set the 2nd true

但是，我意识到当我设置SELECT html元素的名称和ID 而不是 DeliveryStatus时（假设为DeliveryStatus1），它神奇地起作用！

第3个示例（在此处设置所选内容）：

@Html.DropDownList("DeliveryStatus1", new SelectListItem[] {
        new SelectListItem { 
            Selected = false, 
            Text = "Active Delivery", 
            Value = "1" },
        new SelectListItem { 
            Selected = true, 
            Text = "Deactive Delivery", 
            Value = "2" }}) //Notice that I manually set the 2nd true

但是当我这样做并设置为DeliveryStatus1时，我无法将数据发布到Controller。

这有什么问题或我做错了什么？我需要能够设置所选数据并将其重新发送回来

Answer 1

感谢Stephen Muecke，对于enums，我将值设为Enum.ToString()而不是整数值。：

@Html.DropDownListFor(model => model.DeliveryStatus, new SelectListItem[] {
        new SelectListItem { 
            Selected = false, 
            Text = "Active Delivery", 
            Value = "Active" },
        new SelectListItem { 
            Selected = true, 
            Text = "Deactive Delivery", 
            Value = "Deactive" }})

Answer 2

对我有用的是确保model.Xyz变量是一个字符串，然后使用＆＃34; Selected = true＆＃34;使其成为默认选定值。

@Html.DropDownListFor(model => model.TopN, new SelectListItem[]
{
    new SelectListItem() { Text = "10", Value = "10", Selected = false },
    new SelectListItem() { Text = "20", Value = "20", Selected = false },
    new SelectListItem() { Text = "50", Value = "50", Selected = true },
    new SelectListItem() { Text = "100", Value = "100", Selected = false },
    new SelectListItem() { Text = "500", Value = "500", Selected = false }
})

MVC DropDownList NOT设置已选中

2 个答案: