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Accepted
Vladimir
Asked:2021-10-23 04:31:00 +0000 UTC2021-10-23 04:31:00 +0000 UTC

官方文档中示例的奇怪行为

  • 772

我开始阅读有关 Anglesharp 的官方文档，最后一个示例在 JavaScript 和 C# 中以某种奇怪的方式工作。从逻辑上讲，我应该从加载事件中获取文本并从脚本中获取hello，但我只能从 c# 代码中获取它。

编码

using AngleSharp;
using System;
namespace ConsoleApp1
{
    class MyClass
    {
        public async static void EventScriptingExample()
        {
            //We require a custom configuration
            var config = Configuration.Default.WithJs();

            //Create a new context for evaluating webpages with the given config
            var context = BrowsingContext.New(config);

            //This is our sample source, we will trigger the load event
            var source = @"<!doctype html>
        <html>
        <head><title>Event sample</title></head>
        <body>
        <script>
        console.log('Before setting the handler!');

        document.addEventListener('load', function() {
        console.log('Document loaded!');
        });

        document.addEventListener('hello', function() {
        console.log('hello world from JavaScript!');
        });

        console.log('After setting the handler!');
        </script>
        </body>";

            var document = await context.OpenAsync(req => req.Content(source));

            //HTML should be output in the end
            Console.WriteLine(document.DocumentElement.OuterHtml);

            //Register Hello event listener from C# (we also have one in JS)
            document.AddEventListener("hello", (s, ev) =>
            {
                Console.WriteLine("hello world from C#!");
            });

            var e = document.CreateEvent("event");
            e.Init("hello", false, false);
            document.Dispatch(e);
        }


        static void Main()
        {

            EventScriptingExample();
            Console.ReadKey();
        }

    }
}

它应该是：

在此处输入图像描述

我能得到什么：

在此处输入图像描述

注意：也就是说，事件只能从 c# 代码中执行。

javascript

1 个回答

  1. Best Answer

    也许这个例子并不完整。它对我有用：

    using AngleSharp;
using AngleSharp.Js;

    class ConsoleLogger : IConsoleLogger
{
    public void Log(object[] values)
    {
        foreach (object value in values)
            Console.WriteLine(value);
    }
}

class MyClass
{
    public async static Task EventScriptingExample()
    {
        //We require a custom configuration
        var config = Configuration.Default.WithJs().WithConsoleLogger(c => new ConsoleLogger());

        //Create a new context for evaluating webpages with the given config
        var context = BrowsingContext.New(config);

        //This is our sample source, we will trigger the load event
        var source = @"<!doctype html>
    <html>
    <head><title>Event sample</title></head>
    <body>
    <script>
    console.log('Before setting the handler!');

    document.addEventListener('load', function() {
    console.log('Document loaded!');
    });

    document.addEventListener('hello', function() {
    console.log('hello world from JavaScript!');
    });

    console.log('After setting the handler!');
    </script>
    </body>";

        var document = await context.OpenAsync(req => req.Content(source));

        //HTML should be output in the end
        Console.WriteLine(document.DocumentElement.OuterHtml);

        //Register Hello event listener from C# (we also have one in JS)
        document.AddEventListener("hello", (s, ev) =>
        {
            Console.WriteLine("hello world from C#!");
        });

        var e = document.CreateEvent("event");
        e.Init("hello", false, false);
        document.Dispatch(e);
    }

    static async Task Main()
    {
        await EventScriptingExample();
        Console.ReadKey();
    }
}

    我还纠正了异步性，使一切都很漂亮。

    Before setting the handler!
After setting the handler!
Document loaded!
<html><head><title>Event sample</title></head>
    <body>
    <script>
    console.log('Before setting the handler!');

    document.addEventListener('load', function() {
    console.log('Document loaded!');
    });

    document.addEventListener('hello', function() {
    console.log('hello world from JavaScript!');
    });

    console.log('After setting the handler!');
    </script>
    </body></html>
hello world from JavaScript!
hello world from C#!
    • 2

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