Question

在线描述 http://www.mikesdotnetting.com/article/275/custom-taghelpers-in-asp-net-mvc-6如何创建分页标记帮助器。

下面的行

a.InnerHtml = i.ToString ();
li.InnerHtml = a.ToString ();

不起作用。

Error : CS0200 C# Property or indexer 'TagBuilder.InnerHtml' cannot be assigned to -- it is read only

也行

 [TargetElement("pager", Attributes = "total-pages, current-page, url")]

有错误旧的分页选项很容易设置，并且工作正常......但新版本是实施线索

Answer 1

我已经解决了这个问题：

using Microsoft.AspNet.Razor.TagHelpers;
using Microsoft.AspNet.Mvc.Rendering;
using System.Text;
using Microsoft.Extensions.WebEncoders;

namespace MVC6_CustomTagHelper_Demo.TagHelpers
{
    [HtmlTargetElement("pager", Attributes = "total-pages, current-page, link-url")]
    public class PagerTagHelper : TagHelper
    {
        public int CurrentPage { get; set; }
        public int TotalPages { get; set; }
        [HtmlAttributeName("link-url")]
        public string Url { get; set; }
        public override void Process(TagHelperContext context, TagHelperOutput output)
        {

            output.TagName = "div";
            output.PreContent.SetHtmlContent("<ul class=\"link-list\">");

            var items = new StringBuilder();
            for (var i = 1; i <= TotalPages; i++)
            {
                var li = new TagBuilder("li");

                var a = new TagBuilder("a");
                a.MergeAttribute("href", $"{Url}?page={i}");
                a.MergeAttribute("title", $"Click to go to page {i}");
                a.InnerHtml.AppendHtml(i.ToString());
                if (i == CurrentPage)
                {
                    a.AddCssClass("active");
                }

                li.InnerHtml.Append(a);
                var writer = new System.IO.StringWriter();
                li.WriteTo(writer, new HtmlEncoder());
                var s = writer.ToString();
                items.AppendLine(s);
            }
            output.Content.SetHtmlContent(items.ToString());
            output.PostContent.SetHtmlContent("</ul>");
            output.Attributes.Clear();
            output.Attributes.Add("class", "pager");
        }
    }
}

Answer 2

InnerHtml不再有setter，但它现在拥有方法Append，AppendLine，AppendFormat，AppendHtml和AppendHtmlLine 。您可以使用它们将字符串直接注入TagBuilder。

如果您正在扩展Html Razor指令（因此@Html.MyMethod('foo')），第一个特别有用，因为您可以挂钩任何其他Html方法，例如部分。

示例 - 为角度js模板创建实用程序扩展，转换

@Html.AngularTemplate("FooBar")

进入

<script type="text/ng-template" id="foo-bar.html">{{Content of FooBar.cshtml}}</script>

因此 -

using Microsoft.AspNet.Html.Abstractions;
using Microsoft.AspNet.Mvc.Rendering;
using Microsoft.Extensions.WebEncoders;
using System;
using System.Text.RegularExpressions;

...


    public static object AngularTemplate(this IHtmlHelper helper, string templateName)
    {

        var tagBuilder = new TagBuilder("script");
        tagBuilder.MergeAttribute("type", "text/ng-template");
        // turn CamelCase into camel-case
        tagBuilder.MergeAttribute("id", Regex.Replace(templateName, @"([a-z])([A-Z])", "$1-$2").ToLowerInvariant() + ".html");
        tagBuilder.InnerHtml.AppendHtml(helper.Partial(templateName));

        tagBuilder.TagRenderMode = TagRenderMode.Normal;
        tagBuilder.WriteTo(helper.ViewContext.Writer, HtmlEncoder.Default);

        return null;

    }

Pager TagHelper。ASP.NET MVC 6中的新TagHelpers

2 个答案: