如何在c#中将字符串从utf8转换（音译）为ASCII（单字节）？

Question

我有一个字符串对象

“具有多个字符，甚至特殊字符”

我正在尝试使用

UTF8Encoding utf8 = new UTF8Encoding();
ASCIIEncoding ascii = new ASCIIEncoding();

objects 以便将该字符串转换为 ascii。我可以请某人为这个简单的任务带来一些启发吗，那就是狩猎我的下午。

编辑1： 我们想要完成的是摆脱特殊字符，例如一些特殊的 Windows 撇号。我在下面发布的作为答案的代码不会解决这个问题。基本上

奥布莱恩将成为奥布莱恩。其中 ' 是特殊撇号之一

Answer 1

这是对你的另一个问题的回应，看起来它已被删除......这一点仍然成立。

看起来像一个经典的 Unicode 到 ASCII 问题。诀窍是找到它发生的哪里。

.NET 可以很好地使用 Unicode，假设 被告知它是 Unicode 开始（或保留默认值）。

我的猜测是你的接收应用程序无法处理它。所以，我可能会使用 ASCIIEncoder with EncoderReplacementFallback 与 String.Empty:

using System.Text;

string inputString = GetInput();
var encoder = ASCIIEncoding.GetEncoder();
encoder.Fallback = new EncoderReplacementFallback(string.Empty);

byte[] bAsciiString = encoder.GetBytes(inputString);

// Do something with bytes...
// can write to a file as is
File.WriteAllBytes(FILE_NAME, bAsciiString);
// or turn back into a "clean" string
string cleanString = ASCIIEncoding.GetString(bAsciiString); 
// since the offending bytes have been removed, can use default encoding as well
Assert.AreEqual(cleanString, Default.GetString(bAsciiString));

当然，在过去，我们只是循环并删除任何大于 127 的字符……好吧，至少我们这些在美国的人是这样。 ;)

Answer 2

ASCIIEncoding ascii = new ASCIIEncoding();
byte[] byteArray = Encoding.UTF8.GetBytes(sOriginal);
byte[] asciiArray = Encoding.Convert(Encoding.UTF8, Encoding.ASCII, byteArray);
string finalString = ascii.GetString(asciiArray);

让我知道是否有更简单的方法。

Answer 3

using System.Text;

namespace System
{
    public static class StringExtension
    {
        private static readonly ASCIIEncoding asciiEncoding = new ASCIIEncoding();

        public static string ToAscii(this string dirty)
        {
            byte[] bytes = asciiEncoding.GetBytes(dirty);
            string clean = asciiEncoding.GetString(bytes);
            return clean;
        }
    }
}

（系统命名空间，因此它几乎可以自动用于我们所有的字符串。）

Answer 4

using System.Text;

// Create encoder with a replacing encoder fallback
var encoder = ASCIIEncoding.GetEncoding("us-ascii", 
    new EncoderReplacementFallback(string.Empty), 
    new DecoderExceptionFallback());

string cleanString = encoder.GetString(encoder.GetBytes(dirtyString)); 

Answer 5

您必须将变量

targetEncoding

更改为您想要的任何编码。

Encoding targetEncoding = Encoding.GetEncoding(874); // Your target encoding
Encoding utf8 = Encoding.UTF8;

var stringBytes = utf8.GetBytes(Name);
var stringTargetBytes = Encoding.Convert(utf8, targetEncoding, stringBytes);
var ascii8BitRepresentAsCsString = Encoding.GetEncoding("Latin1").GetString(stringTargetBytes);

Answer 6

如果您需要将数据输入另一个不支持 unicode 的系统，这非常有用。通过使用 stringbuilder 和简单循环，代码速度很快（测试处理 8,000 个字符字符串 10,000x = 1.1 秒）。

Address：123 East Tāmaki – Tāmaki“ ” GötheФ€ O’Briens ‘hello’ he said!

输出->

Address:123 East Tamaki - Tamaki" " Gothe O'Briens 'hello' he said!

    /// <summary>
    /// Transliterate all unicode chars to their closest ascii version
    /// Remove/fix accents, maori macrons, typesetters colons, dashes, curly quotes, apostrophes, dashes, invisible spaces, and other bad chars
    /// 1. remove accents but keep the letters
    /// 2. fix punctuation to the closest ascii punctuation
    /// 3. remove any remaining non ascii chars
    /// 4. also remove any invisible control chars
    /// Option: remove line breaks or keep them
    /// </summary>
    /// <example>"CHASSIS NO.：LC0CE4CB3N0345426 East Tāmaki – East Tāmaki“ ” GötheФ€ O’Briens ‘hello’ he said!" outputs "CHASSIS NO.:LC0CE4CB3N0345426 East Tamaki - East Tamaki" " Gothe O'Briens 'hello' he said!"</example>
    public static string CleanUnicodeTransliterateToAscii(string text, bool removeLineBreaks) {
        if (text == null) return null;

        // decomposes accented letters into the letter and the diacritic, fixes wacky punctuation to closest common punctuation
        text = text.Normalize(NormalizationForm.FormKD);

        // loop all chars after converting all punctuation to the closest (fix curly quotes etc)
        var stringBuilder = new StringBuilder();
        foreach (var c in text) {
            var unicodeCategory = CharUnicodeInfo.GetUnicodeCategory(c);
            if (c == '\r' || c == '\n') {
                if (removeLineBreaks) {
                    // skip
                } else {
                    stringBuilder.Append(c);
                }
            } else if (unicodeCategory == UnicodeCategory.Control) {
                // control char - skip
            } else if (unicodeCategory == UnicodeCategory.NonSpacingMark) {
                // diacritic mark/accent - skip             
            } else if (c == '‘' || c == '’') {
                // single curly quote or apostrophe add apostrophe
                stringBuilder.Append("'");
            } else if (unicodeCategory == UnicodeCategory.InitialQuotePunctuation || unicodeCategory == UnicodeCategory.FinalQuotePunctuation) {
                // any other quote add a normal straight quote
                stringBuilder.Append("\"");
            } else if (unicodeCategory == UnicodeCategory.DashPunctuation) {
                stringBuilder.Append("-");
            } else if (unicodeCategory == UnicodeCategory.SpaceSeparator) {
                // add a normal space
                stringBuilder.Append(" ");
            } else if (c > 255) {
                // skip any remaining non ascii chars
            } else {
                stringBuilder.Append(c);
            }
        }
        text = stringBuilder.ToString();
        return text;
    }