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C# Asp.Net MVC下拉列表问题_C#_Asp.net_Asp.net Mvc_Html.dropdownlistfor - Fatal编程技术网

C# Asp.Net MVC下拉列表问题

C# Asp.Net MVC下拉列表问题,c#,asp.net,asp.net-mvc,html.dropdownlistfor,C#,Asp.net,Asp.net Mvc,Html.dropdownlistfor,我试图在我的asp.NETMVC应用程序中显示下拉列表。我在设置列表项的优先级时遇到了麻烦。我犯了什么错 public IList<SelectListItem> Priorities { get; set; } Priorities = new List<SelectListItem>(); Priorities.Add(new IList<SelectListItem> { new S

我试图在我的asp.NETMVC应用程序中显示下拉列表。我在设置列表项的优先级时遇到了麻烦。我犯了什么错

public IList<SelectListItem> Priorities { get; set; }
Priorities = new List<SelectListItem>();
Priorities.Add(new IList<SelectListItem>
                {
                    new SelectListItem { Text = "High", Value = "1"},
                    new SelectListItem { Text = "Low", Value = "0"}
                });

@Html.DropDownListFor(m => m.SelectedPriority, Model.Priorities, "Select one")
public IList优先级{get;set;}
优先级=新列表();
添加(新的IList)
{
新建SelectListItem{Text=“High”,Value=“1”},
新建SelectListItem{Text=“Low”,Value=“0”}
});
@DropDownListFor(m=>m.SelectedPriority,Model.Priorities,“选择一个”)
尝试更改

Priorities = new List<SelectListItem>();
优先级=新列表();

优先级=新列表(){
新建SelectListItem{Text=“High”,Value=“1”},
新建SelectListItem{Text=“Low”,Value=“0”}
};
或铸造和添加范围

 ((List<SelectListItem>)Priorities).AddRange(
                new List<SelectListItem>() {
                    new SelectListItem { Text = "High", Value = "1"},
                    new SelectListItem { Text = "Low", Value = "0"}
                }

            );
((列表)优先级)。添加范围(
新名单(){
新建SelectListItem{Text=“High”,Value=“1”},
新建SelectListItem{Text=“Low”,Value=“0”}
}
);
使用IEnumerable的其他选项:

public IEnumerable<SelectListItem> Priorities { get; set; }
Priorities = new List<SelectListItem>();

Priorities = Priorities.Concat(new List<SelectListItem>() {
                new SelectListItem { Text = "High", Value = "1"},
                new SelectListItem { Text = "Low", Value = "0"}
                }
        );
public IEnumerable Priorities{get;set;}
优先级=新列表();
Priorities=Priorities.Concat(新列表(){
新建SelectListItem{Text=“High”,Value=“1”},
新建SelectListItem{Text=“Low”,Value=“0”}
}
);

此处不能实例化接口:

Priorities.Add(new IList<SelectListItem>
{
    new SelectListItem { Text = "High", Value = "1"},
    new SelectListItem { Text = "Low", Value = "0"}
});
Priorities.Add(新IList)
{
新建SelectListItem{Text=“High”,Value=“1”},
新建SelectListItem{Text=“Low”,Value=“0”}
});
相反,尝试将其实例化为实现IList的东西,并使用AddRange,这是针对这种情况的:

Priorities.AddRange(new List<SelectListItem>
{
  new SelectListItem { Text = "High", Value = "1"},
  new SelectListItem { Text = "Low", Value = "0"}
});
Priorities.AddRange(新列表
{
新建SelectListItem{Text=“High”,Value=“1”},
新建SelectListItem{Text=“Low”,Value=“0”}
});

Change
Priorities.Add(新建IList{..
Priorities.Add(新建SelectListItem{Text=“High”,Value=“1”);
我试图一次添加多个项目。
Priorities.AddRange(new List<SelectListItem>
{
  new SelectListItem { Text = "High", Value = "1"},
  new SelectListItem { Text = "Low", Value = "0"}
});