.NET MVC中为DropDownListFor添加form-style类的位置咨询

No worries, let's break this down so you know exactly where to put that class without any errors!

First, let's recall the parameter order for the DropDownListFor helper method you're using:

1. The expression binding to your model property (m => m.AllowSavePassword)
2. The collection of SelectListItem options
3. The placeholder/empty option text ("Select One")
4. The HTML attributes object (this is where your form-style class belongs!)

You need to pass your new { @class = "form-style" } as the fourth parameter, right after the "Select One" string. Here's the corrected, error-free code:

<label class="control-label">Allow Save Password <span class="text-danger">*</span></label> 
@Html.DropDownListFor(
    m => m.AllowSavePassword, 
    new List<SelectListItem>{ 
        new SelectListItem{Text="Yes", Value="True", Selected=true},
        new SelectListItem{Text="No", Value="False"}
    }, 
    "Select One",
    new { @class = "form-style" } // This is the correct spot!
)

Quick note on ASP.NET MVC HtmlHelper patterns: #

Most built-in HtmlHelper methods (like TextBoxFor, CheckBoxFor, DropDownListFor) reserve their final parameter for an anonymous object where you define HTML attributes—classes, IDs, data attributes, etc. The @ before class is required because class is a reserved keyword in C#; it tells the compiler we're referring to the HTML class attribute, not the C# keyword.

This placement aligns perfectly with the method's expected signature, so you won't get any compilation or runtime errors.

内容的提问来源于stack exchange，提问作者super bird