如何将自定义属性分配给下拉列表

Question

我使用代码创建下拉菜单：

@Html.DropDownListFor(x => x.Material, Model.Materials, new { id = "ddlMaterial", onchange = "DisplayPageChangeMaterial();" })

但是我的选择需要看起来像：

<select name="Material" id="ddlMaterial" onchange="DisplayPageChangeMaterial();" multiple>

注意multiple，它没有值。

我尝试过：

@Html.DropDownListFor(x => x.Material, Model.Materials, new { @multiple, id = "ddlMaterial", onchange = "DisplayPageChangeMaterial();" })

@Html.DropDownListFor(x => x.Material, Model.Materials, new { multiple, id = "ddlMaterial", onchange = "DisplayPageChangeMaterial();" })

@Html.DropDownListFor(x => x.Material, Model.Materials, new { "multiple", id = "ddlMaterial", onchange = "DisplayPageChangeMaterial();" })

全部失败。

Answer 1

您可以用两种方法编写。

1）具有DropDownListFor的对象htmlAttributes>

  @Html.DropDownListFor(x => x.Material, Model.Materials, new { 
  @data_custome = "my attributes values",
  @onchange = "DisplayPageChangeMaterial();",
  @id = "ddlMaterial",
  @multiple = "" })

输出

<select name="Material" 
    data-custome="my attributes values"
    onchange="DisplayPageChangeMaterial();"
    id="ddlMaterial" 
    multiple>

2）带DropDownListFor的IDictionary htmlAttributes>

@Html.DropDownListFor(x => x.Material, Model.Materials, new Dictionary<string, object>() 
{ { "data-custome", "my attributes values" },
{ "onchange", "DisplayPageChangeMaterial();" } ,
{ "id", "ddlMaterial" },
{ "multiple", "" } }
输出

<select name="Material" 
    data-custome="my attributes values"
    onchange="DisplayPageChangeMaterial();"
    id="ddlMaterial" 
    multiple>