How to Escape Unicode Characters in ASCII Strings?

In the ASCII string transit the unicode character

In some programming scenarios, it is a common demand to convert the Unicode character into a rotary ASCII string. This process allows retaining Unicode characters, otherwise it may be lost or replaced by other characters during the encoding process.

For example, a string containing the Unicode character π (PI) needs to be converted into a righteous ASCII format (U03A0). Even if the string is encoded in a system that does not support the Unicode character, this conversion can ensure that the character is retained.

For this reason, any non -ASCII character in the string needs to be replaced with its corresponding transposition sequence. These rigid sequences start with back slope (), and then expressed with the SHPStage of the UNICode code. For example, the unicode code point of π is 03A0, so its rigid sequence becomes U03A0.

The following C#code demonstrates how to use the UXXXX transfers to encodes and decodes non -ASCII characters:

In this code,

<code class="language-csharp">using System;
using System.Text.RegularExpressions;

class Program
{
    static void Main(string[] args)
    {
        string unicodeString = "此函数包含一个Unicode字符pi (\u03a0)";

        Console.WriteLine(unicodeString);

        string encoded = EncodeNonAsciiCharacters(unicodeString);
        Console.WriteLine(encoded);

        string decoded = DecodeEncodedNonAsciiCharacters(encoded);
        Console.WriteLine(decoded);
    }

    static string EncodeNonAsciiCharacters(string value)
    {
        StringBuilder sb = new StringBuilder();
        foreach (char c in value)
        {
            if (c > 127)
            {
                // 此字符对于ASCII来说太大
                string encodedValue = "\u" + ((int)c).ToString("x4");
                sb.Append(encodedValue);
            }
            else
            {
                sb.Append(c);
            }
        }
        return sb.ToString();
    }

    static string DecodeEncodedNonAsciiCharacters(string value)
    {
        return Regex.Replace(
            value,
            @"\u(?<value>[a-zA-Z0-9]{4})",
            m =>
            {
                return ((char)int.Parse(m.Groups["Value"].Value, NumberStyles.HexNumber)).ToString();
            });
    }
}</code>

traverses the input string and recognizes non -ASCII characters, and converts it to its transition sequence. On the other hand, the method uses regular expressions to analyze the string of rotation and convert them back to the original Unicode character.

EncodeNonAsciiCharacters The output of this program shows the process: DecodeEncodedNonAsciiCharacters

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