ASP.NET vNext。通用编辑器模板

Question

在 MVC 5 中，我可以通过创建自定义 Object.cshtml 来自定义通用编辑器模板。

但我在 MVC 6 beta8 中找不到这种行为。

问题：如何在 MVC 6 中自定义通用编辑器模板？

更新：

似乎这个功能是硬编码的。 DefaultEditorTemplates.cs

Answer 1

基于 DefaultEditorTemplates 类，我制作了我的 TagHelper。

也许对某人有用。

ModelTagHelper.cs

[HtmlTargetElement("div", Attributes = ForAttributeName)]
public class ModelTagHelper : TagHelper
{
    protected const string ForAttributeName = "asp-for";
    protected const string ObjectViewPath = "~/Views/Shared/Object.cshtml";

    [HtmlAttributeNotBound]
    [ViewContext]
    public ViewContext ViewContext { get; set; }

    [HtmlAttributeName(ForAttributeName)]
    public ModelExpression For { get; set; }

    public override int Order => -1000;

    protected object Model => For.Model;

    protected IHtmlGenerator HtmlGenerator { get; }
    protected IViewEngine ViewEngine { get; }
    protected ITempDataProvider TempDataProvider { get; }
    protected IHttpContextAccessor HttpContextAccessor { get; }

    public ModelTagHelper(
        ICompositeViewEngine viewEngine, 
        ITempDataProvider tempDataProvider,
        IHttpContextAccessor httpContextAccessor,
        IHtmlGenerator generator)
    {
        HtmlGenerator = generator;
        ViewEngine = viewEngine;
        TempDataProvider = tempDataProvider;
        HttpContextAccessor = httpContextAccessor;
    }

    protected virtual ActionContext CreateActionContext() => new ActionContext(HttpContextAccessor.HttpContext, new RouteData(), new ActionDescriptor());
    protected virtual ViewDataDictionary CreateViewDataDictionary() => new ViewDataDictionary(new EmptyModelMetadataProvider(), new ModelStateDictionary());

    public override void Process(TagHelperContext context, TagHelperOutput output)
    {
        if (context == null)
        {
            throw new ArgumentNullException(nameof(context));
        }

        if (output == null)
        {
            throw new ArgumentNullException(nameof(output));
        }

        using (var sw = new StringWriter())
        {
            var viewDataDictionary = CreateViewDataDictionary();
            viewDataDictionary.Model = Model;

            var actionContext = CreateActionContext();
            var viewResult = ViewEngine.FindPartialView(actionContext, ObjectViewPath);
            if (!viewResult.Success)
            {
                throw new FileNotFoundException("Cannot find the file", ObjectViewPath);
            }
            var viewContext = new ViewContext(
                actionContext,
                viewResult.View,
                viewDataDictionary,
                new TempDataDictionary(HttpContextAccessor, TempDataProvider),
                sw, new HtmlHelperOptions { ClientValidationEnabled = true });
            viewResult.View.RenderAsync(viewContext).Wait();
            sw.Flush();

            output.Content.SetContent(new HtmlString(sw.ToString()));
        }
    }

}

Object.cshmtl

@using Microsoft.AspNet.Mvc.ViewFeatures
@{
var tplInfo = ViewContext.ViewData.TemplateInfo;

Func<ModelExplorer, TemplateInfo, bool> ShouldShow =
    (modelExplorer, templateInfo) =>
    modelExplorer.Metadata.ShowForEdit &&
    !modelExplorer.Metadata.IsComplexType &&
    !templateInfo.Visited(modelExplorer);

var properties = from property in ViewData.ModelExplorer.Properties
                 let propertyMetadata = property.Metadata
                 where ShouldShow(property, tplInfo)
                 select propertyMetadata;

}
@foreach (var propertyMetadata in properties)
{
if (propertyMetadata.HideSurroundingHtml)
{
    @Html.Editor(propertyMetadata.PropertyName)
}
else
{
    var label = Html.Label(propertyMetadata.PropertyName, labelText: null, htmlAttributes: null);
    if (!string.IsNullOrEmpty(label.ToString()))
    {
        <div class="editor-label">
            @label
        </div>
    }
    <div class="editor-field">
        @Html.Editor(propertyMetadata.PropertyName)
        @Html.ValidationMessage(propertyMetadata.PropertyName)
    </div>
}
}

MyView.cshtml

<div asp-for="@Model"></div>

Answer 2

Asp.Net-5 带来了一个名为“TagHelpers”的新功能。

您可以在默认的 MVC6 共享 _Layout.cshtml 页面中看到它们的工作，其中的“环境”标签会根据运行时环境（开发、登台、生产等）产生不同的输出。

您将看到“Microsoft.AspNet.MVC.TagHelpers...”包加载到解决方案资源管理器的“参考”部分中的 DNX 4.5.1 和 DNX Core 5.0 框架部分中。

看起来 TagHelpers 的设计目的是替代“模板”。

在这里快速概览：Wildermuth

还有两篇更深入的文章：MSDN 和 MSDN Mag - 两篇文章

希望对你有所帮助。