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Feed Burner 更改了他们的博客服务返回结果，它返回类似于以下内容的 javascript 块：

document.write("\x3cdiv 类\x3d\x22feedburnerFeedBlock\x22 id\x3d\x22RitterInsuranceMarketingRSSv3iugf6igask14fl8ok645b6l0\x22\x3e"); document.write("\x3cul\x3e"); document.write("\x3cli\x3e\x3cspan 类\x3d\x22headline\x22\x3e\x3ca href\x3d\x22

我想要原始的html。以前我可以轻松地使用 .Replace 来删除 document.write 语法，但我无法弄清楚这是哪种编码或至少如何用 C# 对其进行解码。

编辑：嗯，这是一个最终解决的半噩梦，这就是我想出的，以防有人有任何改进可以提供

public static  char ConvertHexToASCII(this string hex)
{
    if (hex == null) throw new ArgumentNullException(hex);
    return (char)Convert.ToByte(hex, 16);
}

.

private string DecodeFeedburnerHtml(string html)
{
    var builder = new StringBuilder(html.Length);
    var stack = new Stack<char>(4);
    foreach (var chr in html)
    {
        switch (chr)
        {
            case '\\':
                if (stack.Count == 0)
                {
                    stack.Push(chr);
                }
                else
                {
                    stack.Clear();
                    builder.Append(chr);
                }
                break;
            case 'x':
                if (stack.Count == 1)
                {
                    stack.Push(chr);
                }
                else
                {
                    stack.Clear();
                    builder.Append(chr);
                }
                break;
            default:
                if (stack.Count >= 2)
                {
                    stack.Push(chr);

                    if (stack.Count == 4)
                    {
                        //get stack[3]stack[4]
                        string hexString = string.Format("{1}{0}", stack.Pop(),
                                                     stack.Pop());

                        builder.Append(hexString.ConvertHexToASCII());
                        stack.Clear();
                    }
                }
                else
                {
                    builder.Append(chr);
                }
                break;
        }
    }

    html = builder.ToString();
    return html;
}

Not sure what else I could do better. For some reason code like this always feels really dirty to me even though it's a linear time algorithm I guess this is related to how long it has to be.

4

3 回答 3

2

In dotnet core you can use Uri.UnescapeDataString(originalString.Replace("\x","%")) to convert it by making it into a Url encoded string first.

于 2018-03-18T03:08:11.500 回答
1

That is a PHP Twig encoding:

http://www.twig-project.org/

Since you are using C# you will most likely have to create a dictionary to translate the symbols and then use a series of .Replace() string methods to convert those back to HTML characters.

Alternatively you can save that data to a file, run a Perl script to decode the text and then read from the file in C#, but that might be more costly.

于 2010-12-15T20:36:02.540 回答
1

Those look like ASCII values, encoded in hex. You could traverse the string, and whenever you find a \x followed by two hexadecimal digits (0-9,a-f), replace it with the corresponding ASCII character. If the string is long, it would be faster to save the result incrementally to a StringBuilder instead of using String.Replace().

I don't know the encoding specification, but there might be more rules to follow (for example, if \\ is an escape character for a literal \).

于 2010-12-15T20:48:31.897 回答