如何使Uri.EscapeDataString符合RFC 3986

由于无法使Uri.EscapeDataString采用RFC3986行为,我编写了自己的符合RFC3986的转义方法。它利用Uri.EscapeDataString,然后将转义“升级”到RFC 3986法规遵从性。

/// <summary>
/// The set of characters that are unreserved in RFC 2396 but are NOT unreserved in RFC 3986.
/// </summary>
private static readonly string[] UriRfc3986CharsToEscape = new[] { "!", "*", "'", "(", ")" };

/// <summary>
/// Escapes a string according to the URI data string rules given in RFC 3986.
/// </summary>
/// <param name="value">The value to escape.</param>
/// <returns>The escaped value.</returns>
/// <remarks>
/// The <see cref="Uri.EscapeDataString"/> method is <i>supposed</i> to take on
/// RFC 3986 behavior if certain elements are present in a .config file.  Even if this
/// actually worked (which in my experiments it <i>doesn't</i>), we can't rely on every
/// host actually having this configuration element present.
/// </remarks>
internal static string EscapeUriDataStringRfc3986(string value) {
    // Start with RFC 2396 escaping by calling the .NET method to do the work.
    // This MAY sometimes exhibit RFC 3986 behavior (according to the documentation).
    // If it does, the escaping we do that follows it will be a no-op since the
    // characters we search for to replace can't possibly exist in the string.
    StringBuilder escaped = new StringBuilder(Uri.EscapeDataString(value));

    // Upgrade the escaping to RFC 3986, if necessary.
    for (int i = 0; i < UriRfc3986CharsToEscape.Length; i++) {
        escaped.Replace(UriRfc3986CharsToEscape[i], Uri.HexEscape(UriRfc3986CharsToEscape[i][0]));
    }

    // Return the fully-RFC3986-escaped string.
    return escaped.ToString();
}

在.NET4.5中,这实际上已经被修复,默认情况下可以正常工作,请参见 here

PUrify (在遇到这个问题后)这将通过本文中方法的一个变化来处理.NET 4.5之前版本(适用于3.5)和Mono的工作 post . PUrify不会更改EscapeDataString,但它允许您拥有带有保留字符的URI,这些字符不会被转义。

我意识到这个问题和答案已经有几年历史了,但我想当我遇到麻烦时,我会分享我的发现 compliance under .Net 4.5 .

如果您的代码在asp.net下运行,只需将项目设置为目标4.5并在具有4.5或更高版本的计算机上运行,您仍然可能会获得4.0行为。你需要确保 <httpRuntime targetFramework="4.5" /> 在web.config中设置。

从…起 this blog article on msdn ,

如果没有 <httpRuntime targetFramework> 属性存在于 在Web.config中,我们假设应用程序需要4.0怪癖行为。

您使用的是什么版本的框架?看起来这些变化中有很多是在( from MSDN

我找不到更好的答案(无论是100%的框架还是100%的重新实现),所以我创造了这个讨厌的东西。似乎正在与OAuth合作。

class al_RFC3986
{
    public static string Encode(string s)
    {
        StringBuilder sb = new StringBuilder(s.Length*2);//VERY rough estimate
        byte[] arr = Encoding.UTF8.GetBytes(s);

        for (int i = 0; i < arr.Length; i++)
        {
            byte c = arr[i];

            if(c >= 0x41 && c <=0x5A)//alpha
                sb.Append((char)c);
            else if(c >= 0x61 && c <=0x7A)//ALPHA
                sb.Append((char)c);
            else if(c >= 0x30 && c <=0x39)//123456789
                sb.Append((char)c);
            else if (c == '-' || c == '.' || c == '_' || c == '~')
                sb.Append((char)c);
            else
            {
                sb.Append('%');
                sb.Append(Convert.ToString(c, 16).ToUpper());
            }
        }
        return sb.ToString();
    }
}