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Asp.net mvc 设置SelectedListItem的索引_Asp.net Mvc_Razor_Drop Down Menu - Fatal编程技术网

Asp.net mvc 设置SelectedListItem的索引

Asp.net mvc 设置SelectedListItem的索引,asp.net-mvc,razor,drop-down-menu,Asp.net Mvc,Razor,Drop Down Menu,我正在使用as填充下拉列表 [Required(ErrorMessage = "Please make a selection")] public string SelectedPrimary { get; set; } public IEnumerable<SelectListItem> PrimaryDrop { get; set; } public void populateDropdown() { primaryDrop = new

我正在使用as填充下拉列表

[Required(ErrorMessage = "Please make a selection")]
    public string SelectedPrimary { get; set; }
    public IEnumerable<SelectListItem> PrimaryDrop { get; set; }

public void populateDropdown()
    {
        primaryDrop = new List<string>();
        primaryDrop.Insert(0, "Getting ready");
        primaryDrop.Insert(1, "Starting");
        primaryDrop.Insert(2, "All");
        PrimaryDrop = primaryDrop.Select(item => new SelectListItem { Value = item, Text = item });
    }
在检查元素时,我会看到这一点

<select data-val="true" data-val-required="Please make a selection" id="FirstDropDown" name="SelectedPrimary" style="width:207px;">
     <option value="">Learning Path</option>
     <option value="Getting ready">Getting ready</option>
     <option value="Starting">Starting</option>
   <option value="All modules">All</option>
    </select>

学习途径
准备
启动
全部的
如何设置索引的值

<select data-val="true" data-val-required="Please make a selection" id="FirstDropDown" name="SelectedPrimary" style="width:207px;">
     <option value="0">Learning Path</option>
     <option value="1">Getting ready</option>
     <option value="2">Starting</option>
   <option value="3">All modules</option>
    </select>

学习途径
准备
启动
所有模块

您可以这样填充
PrimaryDrop
(用于获取

primaryDrop=newlist();
primaryDrop.Insert(0,“准备就绪”);
primaryDrop.插入(1,“起始”);
primaryDrop.插入(2,“全部”);
PrimaryDrop=PrimaryDrop.Select(项目=>new SelectListItem
{ 
值=primaryDrop.IndexOf(项目),
文本=项目
});

您可以使用字典来构建选择列表。然后使用key作为值,使用value作为文本

var primaryDrop = new Dictionary<string, string>() { 
            {"0", "Getting Ready"},
            {"1", "Starting"},
            {"2", "All"}            
        };
PrimaryDrop = primaryDrop.Select(item => 
    new SelectListItem { Value = item.Key, Text = item.Value });
var primaryDrop=new Dictionary(){
{“0”,“准备就绪”},
{“1”,“开始”},
{“2”,“所有”}
};
PrimaryDrop=PrimaryDrop.Select(项目=>
新建SelectListItem{Value=item.Key,Text=item.Value});
primaryDrop = new List<string>();
primaryDrop.Insert(0, "Getting ready");
primaryDrop.Insert(1, "Starting");
primaryDrop.Insert(2, "All");
PrimaryDrop = primaryDrop.Select(item => new SelectListItem 
{ 
    Value = primaryDrop.IndexOf(item), 
    Text = item 
});
var primaryDrop = new Dictionary<string, string>() { 
            {"0", "Getting Ready"},
            {"1", "Starting"},
            {"2", "All"}            
        };
PrimaryDrop = primaryDrop.Select(item => 
    new SelectListItem { Value = item.Key, Text = item.Value });