如何將文本轉換為 Pascal 大小寫？

Question

我有一個變量名，比如“WARD_VS_VITAL_SIGNS”，我想將其轉換為 Pascal 大小寫格式：“WardVsVitalSigns”

WARD_VS_VITAL_SIGNS -> WardVsVitalSigns

我怎樣才能進行這種轉換？

Answer 1

您不需要正則表達式。

var yourString = "WARD_VS_VITAL_SIGNS".ToLower().Replace("_", " ");
TextInfo info = CultureInfo.CurrentCulture.TextInfo;
yourString = info.ToTitleCase(yourString).Replace(" ", string.Empty);
Console.WriteLine(yourString);

您可以根據需要修改代碼。

Answer 2

這是我的快速LINQ 和正則表達式解決方案，以節省某人的時間：

using System;
using System.Linq;
using System.Text.RegularExpressions;

public string ToPascalCase(string original)
{
    Regex invalidCharsRgx = new Regex("[^_a-zA-Z0-9]");
    Regex whiteSpace = new Regex(@"(?<=\s)");
    Regex startsWithLowerCaseChar = new Regex("^[a-z]");
    Regex firstCharFollowedByUpperCasesOnly = new Regex("(?<=[A-Z])[A-Z0-9]+$");
    Regex lowerCaseNextToNumber = new Regex("(?<=[0-9])[a-z]");
    Regex upperCaseInside = new Regex("(?<=[A-Z])[A-Z]+?((?=[A-Z][a-z])|(?=[0-9]))");

    // replace white spaces with undescore, then replace all invalid chars with empty string
    var pascalCase = invalidCharsRgx.Replace(whiteSpace.Replace(original, "_"), string.Empty)
        // split by underscores
        .Split(new char[] { '_' }, StringSplitOptions.RemoveEmptyEntries)
        // set first letter to uppercase
        .Select(w => startsWithLowerCaseChar.Replace(w, m => m.Value.ToUpper()))
        // replace second and all following upper case letters to lower if there is no next lower (ABC -> Abc)
        .Select(w => firstCharFollowedByUpperCasesOnly.Replace(w, m => m.Value.ToLower()))
        // set upper case the first lower case following a number (Ab9cd -> Ab9Cd)
        .Select(w => lowerCaseNextToNumber.Replace(w, m => m.Value.ToUpper()))
        // lower second and next upper case letters except the last if it follows by any lower (ABcDEf -> AbcDef)
        .Select(w => upperCaseInside.Replace(w, m => m.Value.ToLower()));

    return string.Concat(pascalCase);
}

示例輸出：

"WARD_VS_VITAL_SIGNS"          "WardVsVitalSigns"
"Who am I?"                    "WhoAmI"
"I ate before you got here"    "IAteBeforeYouGotHere"
"Hello|Who|Am|I?"              "HelloWhoAmI"
"Live long and prosper"        "LiveLongAndProsper"
"Lorem ipsum dolor..."         "LoremIpsumDolor"
"CoolSP"                       "CoolSp"
"AB9CD"                        "Ab9Cd"
"CCCTrigger"                   "CccTrigger"
"CIRC"                         "Circ"
"ID_SOME"                      "IdSome"
"ID_SomeOther"                 "IdSomeOther"
"ID_SOMEOther"                 "IdSomeOther"
"CCC_SOME_2Phases"             "CccSome2Phases"
"AlreadyGoodPascalCase"        "AlreadyGoodPascalCase"
"999 999 99 9 "                "999999999"
"1 2 3 "                       "123"
"1 AB cd EFDDD 8"              "1AbCdEfddd8"
"INVALID VALUE AND _2THINGS"   "InvalidValueAnd2Things"

Answer 3

首先，您要求標題大小寫而不是駱駝大小寫，因為在駱駝大小寫中，單詞的第一個字母是小寫，而您的示例顯示您希望第一個字母為大寫。

無論如何，您可以通過以下方式實現您想要的結果：

string textToChange = "WARD_VS_VITAL_SIGNS";
System.Text.StringBuilder resultBuilder = new System.Text.StringBuilder();

foreach(char c in textToChange)
{
    // Replace anything, but letters and digits, with space
    if(!Char.IsLetterOrDigit(c))
    {
        resultBuilder.Append(" ");
    }
    else 
    { 
        resultBuilder.Append(c); 
    }
}

string result = resultBuilder.ToString();

// Make result string all lowercase, because ToTitleCase does not change all uppercase correctly
result = result.ToLower();

// Creates a TextInfo based on the "en-US" culture.
TextInfo myTI = new CultureInfo("en-US",false).TextInfo;

result = myTI.ToTitleCase(result).Replace(" ", String.Empty);

注意： result現在是WardVsVitalSigns 。

如果您確實想要駝峰式大小寫，那么在完成上述所有操作之后，只需使用此輔助函數：

public string LowercaseFirst(string s)
{
    if (string.IsNullOrEmpty(s))
    {
        return string.Empty;
    }

    char[] a = s.ToCharArray();
    a[0] = char.ToLower(a[0]);

    return new string(a);
}

所以你可以這樣稱呼它：

result = LowercaseFirst(result);

Answer 4

單分號解決方案：

public static string PascalCase(this string word)
{
    return string.Join("" , word.Split('_')
                 .Select(w => w.Trim())
                 .Where(w => w.Length > 0)
                 .Select(w => w.Substring(0,1).ToUpper() + w.Substring(1).ToLower()));
}

Answer 5

使用System和System.Linq擴展System.String與 .NET Core 兼容代碼的方法。

不修改原始字符串。

.NET Fiddle 下面的代碼

using System;
using System.Linq;

public static class StringExtensions
{
    /// <summary>
    /// Converts a string to PascalCase
    /// </summary>
    /// <param name="str">String to convert</param>

    public static string ToPascalCase(this string str){

        // Replace all non-letter and non-digits with an underscore and lowercase the rest.
        string sample = string.Join("", str?.Select(c => Char.IsLetterOrDigit(c) ? c.ToString().ToLower() : "_").ToArray());

        // Split the resulting string by underscore
        // Select first character, uppercase it and concatenate with the rest of the string
        var arr = sample?
            .Split(new []{'_'}, StringSplitOptions.RemoveEmptyEntries)
            .Select(s => $"{s.Substring(0, 1).ToUpper()}{s.Substring(1)}");

        // Join the resulting collection
        sample = string.Join("", arr);

        return sample;
    }
}

public class Program
{
    public static void Main()
    {
        Console.WriteLine("WARD_VS_VITAL_SIGNS".ToPascalCase()); // WardVsVitalSigns
        Console.WriteLine("Who am I?".ToPascalCase()); // WhoAmI
        Console.WriteLine("I ate before you got here".ToPascalCase()); // IAteBeforeYouGotHere
        Console.WriteLine("Hello|Who|Am|I?".ToPascalCase()); // HelloWhoAmI
        Console.WriteLine("Live long and prosper".ToPascalCase()); // LiveLongAndProsper
        Console.WriteLine("Lorem ipsum dolor sit amet, consectetur adipiscing elit.".ToPascalCase()); // LoremIpsumDolorSitAmetConsecteturAdipiscingElit
    }
}

Answer 6

var xs = "WARD_VS_VITAL_SIGNS".Split('_');

var q =

    from x in xs

    let first_char = char.ToUpper(x[0]) 
    let rest_chars = new string(x.Skip(1).Select(c => char.ToLower(c)).ToArray())

    select first_char + rest_chars;

Answer 7

有些答案是正確的，但我真的不明白為什么他們首先將文本設置為小寫，因為ToTitleCase會自動處理：

var text = "WARD_VS_VITAL_SIGNS".Replace("_", " ");

TextInfo textInfo = CultureInfo.CurrentCulture.TextInfo;
text = textInfo.ToTitleCase(text).Replace(" ", string.Empty);

Console.WriteLine(text);

Answer 8

你可以使用這個：

public static string ConvertToPascal(string underScoreString)
    {
        string[] words = underScoreString.Split('_');

        StringBuilder returnStr = new StringBuilder();

        foreach (string wrd in words)
        {
            returnStr.Append(wrd.Substring(0, 1).ToUpper());
            returnStr.Append(wrd.Substring(1).ToLower());

        }
        return returnStr.ToString();
    }

Answer 9

如果您確實想將任何格式化字符串替換為帕斯卡大小寫，那么您可以這樣做

    public static string ToPascalCase(this string original)
    {
        string newString = string.Empty;
        bool makeNextCharacterUpper = false;
        for (int index = 0; index < original.Length; index++)
        {
            char c = original[index];
            if(index == 0)
                newString += $"{char.ToUpper(c)}";
            else if (makeNextCharacterUpper)
            {
                newString += $"{char.ToUpper(c)}";
                makeNextCharacterUpper = false;
            }
            else if (char.IsUpper(c))
                newString += $" {c}";
            else if (char.IsLower(c) || char.IsNumber(c))
                newString += c;
            else if (char.IsNumber(c))
                newString += $"{c}";
            else
            {
                makeNextCharacterUpper = true;   
                newString += ' ';
            }
        }

        return newString.TrimStart().Replace(" ", "");
    }

用字符串測試I|Can|Get|A|String ICan_GetAString i-can-get-a-string i_can_get_a_string I Can Get A String ICanGetAString

Answer 10

在向它添加ToLower()后，我發現這個要點很有用。

"WARD_VS_VITAL_SIGNS".ToLower().Split(new [] {"_"}, StringSplitOptions.RemoveEmptyEntries).Select(s => char.ToUpperInvariant(s[0]) + s.Substring(1, s.Length - 1)).Aggregate(string.Empty, (s1, s2) => s1 + s2)

Answer 11

這個答案明白在處理文本時可以點擊 Unicode 類別以忽略連接字符，例如-或_ 。 在正則表達式中，它是\\p （用於類別）然后是{Pc}用於標點符號和連接符類型字符的類型； \\p{Pc} 。

所以我們只替換單詞並忽略替換中的標點符號。 一旦我們有了這個詞，把它向下推到小寫，把第一個字符大寫：

public static class StringExtensions
{
    public static string ToPascalCase(this string initial)
        => Regex.Replace(initial, 
                         // (Match any non punctuation) & then ignore any punctuation
                         @"([^\p{Pc}]+)[\p{Pc}]*", 
                         new MatchEvaluator(mtch =>
        {
            var word = mtch.Groups[1].Value.ToLower();

            return $"{Char.ToUpper(word[0])}{word.Substring(1)}";
        }));
}

用法：

"TOO_MUCH_BABY".ToPascalCase(); // TooMuchBaby
"HELLO|ITS|ME".ToPascalCase();  // HelloItsMe

---

請參閱正則表達式中字符類中的單詞字符

Pc 標點符號，連接器。 該類別包括十個字符，其中最常用的是LOWLINE字符（_），u+005F。