将字符串转换为标题大小写

MSDN：TextInfo.ToTitleCase

确保包括：using System.Globalization

string title = "war and peace";

TextInfo textInfo = new CultureInfo("en-US", false).TextInfo;

title = textInfo.ToTitleCase(title); 
Console.WriteLine(title) ; //War And Peace

//When text is ALL UPPERCASE...
title = "WAR AND PEACE" ;

title = textInfo.ToTitleCase(title); 
Console.WriteLine(title) ; //WAR AND PEACE

//You need to call ToLower to make it work
title = textInfo.ToTitleCase(title.ToLower()); 
Console.WriteLine(title) ; //War And Peace

---

尝试这个：

string myText = "a Simple string";

string asTitleCase =
    System.Threading.Thread.CurrentThread.CurrentCulture.TextInfo.
    ToTitleCase(myText.ToLower());

正如已经指出的那样，使用 TextInfo.ToTitleCase 可能无法为您提供所需的确切结果。如果您需要对输出进行更多控制，可以执行以下操作：

IEnumerable<char> CharsToTitleCase(string s)
{
    bool newWord = true;
    foreach(char c in s)
    {
        if(newWord) { yield return Char.ToUpper(c); newWord = false; }
        else yield return Char.ToLower(c);
        if(c==' ') newWord = true;
    }
}

然后像这样使用它：

var asTitleCase = new string( CharsToTitleCase(myText).ToArray() );

---

又一个变种。基于此处的几个提示，我将其简化为这种扩展方法，这对我的目的非常有用：

public static string ToTitleCase(this string s) =>
    CultureInfo.InvariantCulture.TextInfo.ToTitleCase(s.ToLower());

---

我个人尝试了 TextInfo.ToTitleCase 方法，但是，我不明白为什么当所有字符都大写时它不起作用。

虽然我喜欢 Winston Smith 提供的 util 函数，但让我提供我目前正在使用的函数：

public static String TitleCaseString(String s)
{
    if (s == null) return s;

    String[] words = s.Split(' ');
    for (int i = 0; i < words.Length; i++)
    {
        if (words[i].Length == 0) continue;

        Char firstChar = Char.ToUpper(words[i][0]); 
        String rest = "";
        if (words[i].Length > 1)
        {
            rest = words[i].Substring(1).ToLower();
        }
        words[i] = firstChar + rest;
    }
    return String.Join(" ", words);
}

玩一些测试字符串：

String ts1 = "Converting string to title case in C#";
String ts2 = "C";
String ts3 = "";
String ts4 = "   ";
String ts5 = null;

Console.Out.WriteLine(String.Format("|{0}|", TitleCaseString(ts1)));
Console.Out.WriteLine(String.Format("|{0}|", TitleCaseString(ts2)));
Console.Out.WriteLine(String.Format("|{0}|", TitleCaseString(ts3)));
Console.Out.WriteLine(String.Format("|{0}|", TitleCaseString(ts4)));
Console.Out.WriteLine(String.Format("|{0}|", TitleCaseString(ts5)));

给出输出：

|Converting String To Title Case In C#|
|C|
||
|   |
||

---

最近我找到了一个更好的解决方案。

如果您的文本包含大写的每个字母，则 TextInfo 不会将其转换为正确的大小写。我们可以通过使用内部的小写函数来解决这个问题，如下所示：

public static string ConvertTo_ProperCase(string text)
{
    TextInfo myTI = new CultureInfo("en-US", false).TextInfo;
    return myTI.ToTitleCase(text.ToLower());
}

现在这会将所有进入的内容转换为 Propercase。

---

public static string PropCase(string strText)
{
    return new CultureInfo("en").TextInfo.ToTitleCase(strText.ToLower());
}

---

首先使用 ToLower()，然后对结果使用 CultureInfo.CurrentCulture.TextInfo.ToTitleCase 以获得正确的输出。

    //---------------------------------------------------------------
    // Get title case of a string (every word with leading upper case,
    //                             the rest is lower case)
    //    i.e: ABCD EFG -> Abcd Efg,
    //         john doe -> John Doe,
    //         miXEd CaSING - > Mixed Casing
    //---------------------------------------------------------------
    public static string ToTitleCase(string str)
    {
        return CultureInfo.CurrentCulture.TextInfo.ToTitleCase(str.ToLower());
    }

---

如果有人对 Compact Framework 的解决方案感兴趣：

return String.Join(" ", thestring.Split(' ').Select(i => i.Substring(0, 1).ToUpper() + i.Substring(1).ToLower()).ToArray());

---

这是该问题的解决方案...

CultureInfo cultureInfo = Thread.CurrentThread.CurrentCulture;
TextInfo textInfo = cultureInfo.TextInfo;
string txt = textInfo.ToTitleCase(txt);

---

我需要一种处理所有大写单词的方法，并且我喜欢 Ricky AH 的解决方案，但我更进一步将其实现为扩展方法。这避免了必须创建字符数组然后每次显式调用 ToArray 的步骤 - 所以你可以在字符串上调用它，如下所示：

用法：

string newString = oldString.ToProper();

代码：

public static class StringExtensions
{
    public static string ToProper(this string s)
    {
        return new string(s.CharsToTitleCase().ToArray());
    }

    public static IEnumerable<char> CharsToTitleCase(this string s)
    {
        bool newWord = true;
        foreach (char c in s)
        {
            if (newWord) { yield return Char.ToUpper(c); newWord = false; }
            else yield return Char.ToLower(c);
            if (c == ' ') newWord = true;
        }
    }

}

---

通过尝试自己的代码更好地理解......

阅读更多

http://www.stupidcodes.com/2014/04/convert-string-to-uppercase-proper-case.html

1) 将字符串转换为大写

string lower = "converted from lowercase";
Console.WriteLine(lower.ToUpper());

2) 将字符串转换为小写

string upper = "CONVERTED FROM UPPERCASE";
Console.WriteLine(upper.ToLower());

3) 将字符串转换为 TitleCase

    CultureInfo cultureInfo = Thread.CurrentThread.CurrentCulture;
    TextInfo textInfo = cultureInfo.TextInfo;
    string txt = textInfo.ToTitleCase(TextBox1.Text());

---

我使用了上述参考资料，完整的解决方案是：

Use Namespace System.Globalization;
string str = "INFOA2Z means all information";

// 需要像“Infoa2z 表示所有信息”这样的结果 // 我们还需要将字符串转换为小写，否则无法正常工作。

TextInfo ProperCase = new CultureInfo("en-US", false).TextInfo;

str = ProperCase.ToTitleCase(str.toLower());

Change string to proper case in an ASP.NET Using C#

---

String TitleCaseString(String s)
{
    if (s == null || s.Length == 0) return s;

    string[] splits = s.Split(' ');

    for (int i = 0; i < splits.Length; i++)
    {
        switch (splits[i].Length)
        {
            case 1:
                break;

            default:
                splits[i] = Char.ToUpper(splits[i][0]) + splits[i].Substring(1);
                break;
        }
    }

    return String.Join(" ", splits);
}

---

不使用 TextInfo：

public static string TitleCase(this string text, char seperator = ' ') =>
  string.Join(seperator, text.Split(seperator).Select(word => new string(
    word.Select((letter, i) => i == 0 ? char.ToUpper(letter) : char.ToLower(letter)).ToArray())));

它遍历每个单词中的每个字母，如果它是第一个字母则将其转换为大写，否则将其转换为小写。

---

在检查 null 或空字符串值以消除错误后，您可以使用此简单方法直接将文本或字符串更改为正确：

// Text to proper (Title Case):
    public string TextToProper(string text)
    {
        string ProperText = string.Empty;
        if (!string.IsNullOrEmpty(text))
        {
            ProperText = CultureInfo.CurrentCulture.TextInfo.ToTitleCase(text);
        }
        else
        {
            ProperText = string.Empty;
        }
        return ProperText;
    }

---

参考 Microsoft.VisualBasic 的替代方案（也处理大写字符串）：

string properCase = Strings.StrConv(str, VbStrConv.ProperCase);

---

这是一个逐字符的实现。它应该与“（一二三）”一起使用：

public static string ToInitcap(this string str)
{
    if (string.IsNullOrEmpty(str))
        return str;
    char[] charArray = new char[str.Length];
    bool newWord = true;
    for (int i = 0; i < str.Length; ++i)
    {
        Char currentChar = str[i];
        if (Char.IsLetter(currentChar))
        {
            if (newWord)
            {
                newWord = false;
                currentChar = Char.ToUpper(currentChar);
            }
            else
            {
                currentChar = Char.ToLower(currentChar);
            }
        }
        else if (Char.IsWhiteSpace(currentChar))
        {
            newWord = true;
        }
        charArray[i] = currentChar;
    }
    return new string(charArray);
}

---

尝试这个：

using System.Globalization;
using System.Threading;
public void ToTitleCase(TextBox TextBoxName)
        {
            int TextLength = TextBoxName.Text.Length;
            if (TextLength == 1)
            {
                CultureInfo cultureInfo = Thread.CurrentThread.CurrentCulture;
                TextInfo textInfo = cultureInfo.TextInfo;
                TextBoxName.Text = textInfo.ToTitleCase(TextBoxName.Text);
                TextBoxName.SelectionStart = 1;
            }
            else if (TextLength > 1 && TextBoxName.SelectionStart < TextLength)
            {
                int x = TextBoxName.SelectionStart;
                CultureInfo cultureInfo = Thread.CurrentThread.CurrentCulture;
                TextInfo textInfo = cultureInfo.TextInfo;
                TextBoxName.Text = textInfo.ToTitleCase(TextBoxName.Text);
                TextBoxName.SelectionStart = x;
            }
            else if (TextLength > 1 && TextBoxName.SelectionStart >= TextLength)
            {
                CultureInfo cultureInfo = Thread.CurrentThread.CurrentCulture;
                TextInfo textInfo = cultureInfo.TextInfo;
                TextBoxName.Text = textInfo.ToTitleCase(TextBoxName.Text);
                TextBoxName.SelectionStart = TextLength;
            }
        }

在 TextBox 的 TextChanged 事件中调用此方法。

---

这是我使用的，它适用于大多数情况，除非用户决定通过按下 shift 或 caps lock 来覆盖它。就像在 Android 和 iOS 键盘上一样。

Private Class ProperCaseHandler
    Private Const wordbreak As String = " ,.1234567890;/\-()#$%^&*€!~+=@"
    Private txtProperCase As TextBox

    Sub New(txt As TextBox)
        txtProperCase = txt
        AddHandler txt.KeyPress, AddressOf txtTextKeyDownProperCase
    End Sub

    Private Sub txtTextKeyDownProperCase(ByVal sender As System.Object, ByVal e As Windows.Forms.KeyPressEventArgs)
        Try
            If Control.IsKeyLocked(Keys.CapsLock) Or Control.ModifierKeys = Keys.Shift Then
                Exit Sub
            Else
                If txtProperCase.TextLength = 0 Then
                    e.KeyChar = e.KeyChar.ToString.ToUpper()
                    e.Handled = False
                Else
                    Dim lastChar As String = txtProperCase.Text.Substring(txtProperCase.SelectionStart - 1, 1)

                    If wordbreak.Contains(lastChar) = True Then
                        e.KeyChar = e.KeyChar.ToString.ToUpper()
                        e.Handled = False
                    End If
                End If

            End If

        Catch ex As Exception
            Exit Sub
        End Try
    End Sub
End Class

---

作为扩展方法：

/// <summary>
//     Returns a copy of this string converted to `Title Case`.
/// </summary>
/// <param name="value">The string to convert.</param>
/// <returns>The `Title Case` equivalent of the current string.</returns>
public static string ToTitleCase(this string value)
{
    string result = string.Empty;

    for (int i = 0; i < value.Length; i++)
    {
        char p = i == 0 ? char.MinValue : value[i - 1];
        char c = value[i];

        result += char.IsLetter(c) && ((p is ' ') || p is char.MinValue) ? $"{char.ToUpper(c)}" : $"{char.ToLower(c)}";
    }

    return result;
}

用法：

"kebab is DELICIOU's   ;d  c...".ToTitleCase();

结果：

Kebab Is Deliciou's ;d C...

---

即使使用骆驼案，它也能正常工作：'someText in YourPage'

public static class StringExtensions
{
    /// <summary>
    /// Title case example: 'Some Text In Your Page'.
    /// </summary>
    /// <param name="text">Support camel and title cases combinations: 'someText in YourPage'</param>
    public static string ToTitleCase(this string text)
    {
        if (string.IsNullOrEmpty(text))
        {
            return text;
        }
        var result = string.Empty;
        var splitedBySpace = text.Split(new[]{ ' ' }, StringSplitOptions.RemoveEmptyEntries);
        foreach (var sequence in splitedBySpace)
        {
            // let's check the letters. Sequence can contain even 2 words in camel case
            for (var i = 0; i < sequence.Length; i++)
            {
                var letter = sequence[i].ToString();
                // if the letter is Big or it was spaced so this is a start of another word
                if (letter == letter.ToUpper() || i == 0)
                {
                    // add a space between words
                    result += ' ';
                }
                result += i == 0 ? letter.ToUpper() : letter;
            }
        }
        return result.Trim();
    }
}

---

对于那些希望在按键上自动执行此操作的人，我在自定义文本框控件上使用 VB.NET 中的以下代码完成了它 - 您显然也可以使用普通文本框来执行此操作 - 但我喜欢为特定添加重复代码的可能性通过自定义控件控制它适合 OOP 的概念。

Imports System.Windows.Forms
Imports System.Drawing
Imports System.ComponentModel

Public Class MyTextBox
    Inherits System.Windows.Forms.TextBox
    Private LastKeyIsNotAlpha As Boolean = True
    Protected Overrides Sub OnKeyPress(e As KeyPressEventArgs)
        If _ProperCasing Then
            Dim c As Char = e.KeyChar
            If Char.IsLetter(c) Then
                If LastKeyIsNotAlpha Then
                    e.KeyChar = Char.ToUpper(c)
                    LastKeyIsNotAlpha = False
                End If
            Else
                LastKeyIsNotAlpha = True
            End If
        End If
        MyBase.OnKeyPress(e)
End Sub
    Private _ProperCasing As Boolean = False
    <Category("Behavior"), Description("When Enabled ensures for automatic proper casing of string"), Browsable(True)>
    Public Property ProperCasing As Boolean
        Get
            Return _ProperCasing
        End Get
        Set(value As Boolean)
            _ProperCasing = value
        End Set
    End Property
End Class

---

在 C 中执行此操作的方法：

char proper(char string[])
{
    int i = 0;

    for(i=0; i<=25; i++)
    {
        string[i] = tolower(string[i]);  // Converts all characters to lower case
        if(string[i-1] == ' ') // If the character before is a space
        {
            string[i] = toupper(string[i]); // Converts characters after spaces to upper case
        }
    }

    string[0] = toupper(string[0]); // Converts the first character to upper case
    return 0;
}

---