MVC 3 - 从服务器端获取javascript上下拉列表中的值

Question

我有一个javascript,可以从我的下拉列表中更改值,当我保存表单时,无法在服务器端捕获该值.

下面是一些代码:

  <div class="editor-field">
    @Html.DropDownListFor(model => model.CategoriaId,
        Model.Categorias
            .Where(c => c.Id != Model.ContentId)
            .Select(c => new SelectListItem {
                Selected = c.Id == Model.CategoriaId,
                Text = c.Type + " - " +c.Name,
                Value = c.Id.ToString()
            } ),
            "Selecione uma Categoria")

         @Html.Hidden("hdnValue", Model.hndCategoriaId) // my hidden value
  </div>

更改下拉列表和隐藏值的Javascript

function change(item) {

var valueArtigo;
var ddl = document.getElementById('Categoria_CategoriaId');         
for (i = 0; i < ddl.options.length; i++) {
   if (ddl.options[i].text.toUpperCase().indexOf("ARTIGOS") != -1)
   valueArtigo = ddl.options[i].value;
}
document.getElementById("Categoria_CategoriaId").value = valueArtigo;
document.getElementById("Categoria_hdnValue").value = valueArtigo;
}

回到服务器端,我试图保存数据库的价值.

public void UpdateCategoriaForContentItem(ContentItem item, EditCategoriaViewModel model)
{
    if ((model.CategoriaId != null)||(model.hndCategoriaId != null)) // both are null
    {...}
}

谢谢,

Answer 1

您需要将隐藏值绑定到模型

@Html.HiddenFor(m=>m.hdnCategoriaId)
or
@Html.Hidden("hdnCategoriaId",Model.hdnCategoriaId,Model)

要在下拉列表更改事件中设置隐藏字段的值,您可以这样做

$('#hdnCategoriaId').val(valueArtigo)