Creating custom Tag Helpers

To use all the custom TagHelper that we will create in this chapter, you need to refer to the current assembly to tell the framework where to find the TagHelper. Open the _ViewImports.cshtml file in the View/ folder and add the following line at the end of the file:

@addTagHelper *, TagHelperSample

Here's a quick example showing how to extend an existing tag using a TagHelper:

1. Let's assume we need to have a tag configured in bold and colored in a specific color:

   <p strong color="red">Use this area to provide 
     additional information.</p>

This looks like pretty old-fashioned HTML from the 90s, but this is just to demonstrate a simple TagHelper.

2. The current method to do this task is to use a TagHelper to extend any tag that has an attribute called strong, as shown in the following code snippet:

   using Microsoft.AspNetCore.Razor.TagHelpers;
    
   namespace TagHelperSample.TagHelpers;
   [HtmlTargetElement...