Is Html Agility Pack compatible with Blazor applications?

Yes, the Html Agility Pack (HAP) is compatible with Blazor applications, but there are some considerations to keep in mind.

The Html Agility Pack is a .NET library that is used to parse and manipulate HTML documents. It is commonly used in .NET applications for tasks such as web scraping, reading and updating HTML files, and more. Because Blazor is a web framework within the .NET ecosystem, you can use HAP in server-side Blazor applications (Blazor Server) without any issues.

Here's an example of how you could use Html Agility Pack in a Blazor server-side application:

// Add the Html Agility Pack NuGet package
// In your NuGet package manager console, run:
// Install-Package HtmlAgilityPack

using HtmlAgilityPack;
using System.Net.Http;
using System.Threading.Tasks;

public class HtmlScraperService
{
    private readonly HttpClient _httpClient;

    public HtmlScraperService(HttpClient httpClient)
    {
        _httpClient = httpClient;
    }

    public async Task<HtmlDocument> LoadHtmlFromUrlAsync(string url)
    {
        var response = await _httpClient.GetAsync(url);
        var pageContents = await response.Content.ReadAsStringAsync();

        var htmlDoc = new HtmlDocument();
        htmlDoc.LoadHtml(pageContents);

        return htmlDoc;
    }
}

// You can then use this service in your Blazor components or services to parse HTML.

However, Html Agility Pack cannot be used in Blazor WebAssembly (Blazor WASM) directly because it relies on .NET APIs that may not be supported or could cause issues when running in the browser's WebAssembly environment.

For Blazor WebAssembly, you would need to make an API call to a server-side endpoint (which could be a Blazor Server app, an ASP.NET Core app, Azure Function, etc.) that performs the HTML parsing using HAP and then returns the results to the Blazor WebAssembly application.

Here is an example of how you could set up a server-side API endpoint using ASP.NET Core:

// In your ASP.NET Core controller:

[ApiController]
[Route("api/[controller]")]
public class HtmlParsingController : ControllerBase
{
    [HttpGet("parse")]
    public ActionResult ParseHtmlFromUrl(string url)
    {
        // Use Html Agility Pack to parse the HTML from the given URL
        // Return the parsed data or some results back to the Blazor WebAssembly app
    }
}

And then you would call this endpoint from your Blazor WebAssembly application:

// In your Blazor WebAssembly component or service:

@inject HttpClient HttpClient

private async Task CallHtmlParsingApi(string url)
{
    var response = await HttpClient.GetAsync($"api/htmlparsing/parse?url={url}");
    if (response.IsSuccessStatusCode)
    {
        // Handle the parsed HTML data returned from the server
    }
    else
    {
        // Handle error
    }
}

In summary, Html Agility Pack can be used within Blazor Server applications directly, but for Blazor WebAssembly, you will need to perform HTML parsing on the server side and interact with the Blazor WASM app through API calls.