asp.net-mvc - Kendo DropDownList 默认选定值

Question

我有一个 Kendo DropDownList:

@(Html.Kendo().DropDownList()
    .Name("concessions")
    .HtmlAttributes(new { style = "width:320px" })
    .DataTextField("Description")
    .DataValueField("Id")
    .DataSource(source =>
    {
        source.Read(read =>
        {
            read.Action("getConcessionsDDL", "MasterData");
        });
    })
)

数据源是从 Controller 中的 getConcessionsDDL 方法读取的:

public ActionResult GetConcessionsDDL()
{
    ConcessionModel cm = new ConcessionModel();
    var aux = cm.getConcessions();
    return Json(aux.concessions.Select(sme => new ConcessionModel { Description = sme.concession.mediumDescription, Id = sme.concession.id }).Distinct(), JsonRequestBehavior.AllowGet);
}

它工作正常，DropDownList 已按预期填充。但现在我想定义它的默认选择值。现在，默认值始终是列表的第一个。

我使用了 .SelectedIndex(4) 并且它有效:在本例中，所选索引将为 4。但我想在 Controller 中定义它。

我尝试在 ViewBag 中传递选定的索引，但没有成功:

ViewBag.selectedIndex = 21;

在 View 中:

@(Html.Kendo().DropDownList()
    .Name("concessions")
    .HtmlAttributes(new { style = "width:320px" })
    .DataTextField("Description")
    .DataValueField("Id")
    .DataSource(source =>
    {
        source.Read(read =>
        {
            read.Action("getConcessionsDDL", "MasterData");
        });
    })
    .SelectedIndex(ViewBag.selectedIndex)
)

到目前为止还没有运气。有什么帮助吗？

Answer 1

解决方案很简单，将值添加为 HTML 属性即可正常工作:

.HtmlAttributes(new { value = ViewBag.ConcessionId })

像这样:

@(Html.Kendo().DropDownList()
    .Name("concessions")
    .HtmlAttributes(new { style = "width:320px" })
    .DataTextField("Description")
    .HtmlAttributes(new { value = ViewBag.ConcessionId })
    .DataValueField("Id")
    .DataSource(source =>
    {
        source.Read(read =>
        {
            read.Action("getConcessionsDDL", "MasterData");
        });
    })
)