asp.net core 自定义 TagHelper

"date" : "2020-05-25 13:58:25"
"classfiy" : "asp.net core"
"author" : "飞扬"
"viewTimes" : 287

官方文档：[点击查看](https://docs.microsoft.com/zh-cn/aspnet/core/mvc/views/tag-helpers/authoring?view=aspnetcore-3.1 "点击查看")
&gt;发现的问题：
好像不能更改项目的namespace，更改了就无效了，我也不知道什么情况。。

```c#
//TagHelpers\MyTagHelper.cs
using Microsoft.AspNetCore.Razor.TagHelpers;
namespace FysmartBlog.TagHelpers
{
    [HtmlTargetElement("blog")]
    public class BlogTagHelper : TagHelper
    {
        [HtmlAttributeName("b-action")]
        public string Action { get; set; }
        [HtmlAttributeName("b-id")]
        public string BlogId { get; set; }
        [HtmlAttributeName("b-title")]
        public string BlogTitle { get; set; }
        [HtmlAttributeName("b-fragment")]
        public string fragment { get; set; }

public override void Process(TagHelperContext context, TagHelperOutput output)
        {
            output.TagName = "a";
            if (string.IsNullOrEmpty(Action))
            {
                if (!string.IsNullOrEmpty(BlogId))
                    Action = "details";
                else
                    Action = "index";
            }
            var href = $"/{Action.ToLower()}/{BlogId}";
            if (Action == "index")
                href = "/";
            if (!string.IsNullOrEmpty(fragment))
                href += "#" + fragment;
            output.Attributes.SetAttribute("href", href);
            if (!string.IsNullOrEmpty(BlogTitle))
                output.Content.SetContent(BlogTitle);
        }
    }
}
```
```c#
//Views\_ViewImports.cshtml
using FysmartBlog
@addTagHelper *, FysmartBlog
```