C＃中是否有用于跟踪字符级元数据（标签）的字符串的内置功能？

Question

C＃中是否有一些类似字符串的类，并允许我存储某些字符/单词的自定义元数据（标签）？

例如，对于字符串Example string，我可能想要添加大写字母E 大写字母的信息，我可能想添加一些字母的类型（比如说） vocals ）。然后我可能想在字符串上调用.Replace或.Trim，我需要结果仍然包含序列中未更改字母的'tags'。

在C＃/ .NET中是否可以这样，而不必自己编写所有逻辑？

Answer 1

“有什么内置”的答案是否定的。

但是，您可以创建自己的类来处理所需的任何元数据信息结构，并将string值公开为内部属性。您也可以使用它来覆盖ToString()方法。通过这种方式，您将能够传递您的对象并仍使用其string等效对象。

通过重载运算符，您还可以对常规string实例进行转换和比较。

Answer 2

只是为了它的乐趣！

快速运行：

1. 下载永远令人惊叹的LinqPad
2. 打开它并选择Language C# Program
3. 粘贴以下代码
4. 按 Alt + X

---

void Main()
{
    string str = "Example, string";
    var output = Explain(str);

    OutputExplanation(output);
}

private void OutputExplanation(List<LetterExplanation> input)
{
    StringBuilder sb = new StringBuilder();

    foreach(var ltr in input)
        sb.AppendFormat("The letter {0} is {1}\n", ltr.Letter, ltr.Type);

    sb.ToString().Dump();
}

private List<LetterExplanation> Explain(string input) 
{
    var sb = new List<LetterExplanation>();

    foreach(char c in input.ToCharArray())
    {
        //c.Dump(); 
        LetterType type = LetterType.Character;

        // vowel, consonant or special
        if("aeiou".IndexOf(c.ToString(), StringComparison.InvariantCultureIgnoreCase) >= 0)
            type |= LetterType.Vowel;
        else if(" ,.-_<>/\\".IndexOf(c.ToString(), StringComparison.InvariantCultureIgnoreCase) >= 0)
            type |= LetterType.Special;
        else
            type |= LetterType.Consonant;

        // uppercase or lowercase
        if(char.IsUpper(c) && (type & LetterType.Special) != LetterType.Special)
            type |= LetterType.Uppercase;
        else if((type & LetterType.Special) != LetterType.Special)
            type |= LetterType.Lowercase;

        // add
        sb.Add(new LetterExplanation() { Letter = c, Type = type });
    }

    return sb;
} 

[Flags]
public enum LetterType {
    Vowel = 1, Consonant = 1 << 1, Uppercase = 1 << 2, Lowercase = 1 << 3, Number = 1 << 4, Special = 1 << 5, Character = 1 << 6
}

public class LetterExplanation
{
    public char Letter { get; set; }
    public LetterType Type { get; set; }
}

您的输出结果为：

The letter E is Vowel, Uppercase, Character
The letter x is Consonant, Lowercase, Character
The letter a is Vowel, Lowercase, Character
The letter m is Consonant, Lowercase, Character
The letter p is Consonant, Lowercase, Character
The letter l is Consonant, Lowercase, Character
The letter e is Vowel, Lowercase, Character
The letter , is Special, Character
The letter   is Special, Character
The letter s is Consonant, Lowercase, Character
The letter t is Consonant, Lowercase, Character
The letter r is Consonant, Lowercase, Character
The letter i is Vowel, Lowercase, Character
The letter n is Consonant, Lowercase, Character
The letter g is Consonant, Lowercase, Character

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