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());

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())));

它循环每个单词中的每个字母，如果它是第一个字母，则将其转换为大写字母，否则将其转换为小写字母。

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…

就我个人而言，我尝试了TextInfo。ToTitleCase方法，但是，我不明白为什么当所有字符都是大写的时候它不起作用。

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)));

给输出:

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

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

试试这个:

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。